I am having trouble in math...it is a distance learning program and they dont give enough instructions?

I am having trouble in math...it is a distance learning program and they dont give enough instructions..please help me..thank you in advance for those of you who help. 1. What is the slope of the line passing through the points (4,0) and (4,5). 2. Given f(x) =5x^(second power) - 3x+1, find f(-2). 3. Rewrite the equation 4x-6y=-30 as a function of x. 4. Write the equation of the line passing through (3,-7) and (-6,-7) 5. Write the equation of the line that passes through point (-2,3) with a slope of -4. 6. Find the slope of the line through the following pairs of points (-6,1) and (3,1) 7. Find the slope and y-intercept of the line represented by each of the following equations. 2x+5y=10 8.Determine which two equations represent perpendicular lines. (a) y=5/9x - 6 (b) y= 6x-5/9 (c) y= -1/6x + 5/9 (d) y= 1/6x - 5/9 9. Are the following pairs of lines parallel, perpendicular, or neither? L1 through (-2,4) and (1,8) L1 through (-1,-1) and (-5,2)

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  1. Well, it's been a while and I'm not doing your homework for you, however, the first one needs to be solved as a simple rise over run equation or y=mx+b. The third one needs solved for x by dividing each side by 4 and adding 6y to each side. remember what is done to one side must be done to the other. number 5,6, 7 need solved as the first one and humber 8 and 9 need graphed.
  2. 1) m = slope m=rise/run x1=4, x2=4, y1=0, y2=5 rise/run = y2-y1/x2-x1 m= (0-5)/(4-4) m=-5/0 m is undefined, there is no slope Think about it for a moment. You have two points, the first point is at 4 and 0, the second point is at 4 and 5, no slope. 2) f(x) = 5x^2 – 3x + 1 plug in –2 for x 5 (-2^2) – 3 (-2) + 1 20 – (-6) + 1 26 + 1 27 when f(x) = -2 3) 4x - 6y= -30 4x = 6y – 30 x = (6y – 30)/4 x = 3/2y – 7.5 4) (3,-7) and (-6,-7) y = mx + b solve for the slope, m = [(-7) – (-7)]/ [(-6) – 3] m = 0/-9 well what do you know, another dead end! You must first have a definitive line in order to have an equation. Don’t quote me, it has been about 35 years since I took 9th grade algebra. I’ll leave the rest for you smart guys.
  3. Looks like we are asked to do your whole lesson! It won't help unless you receive the explanations you're looking for. Don't try to rush through the explanation too fast; reading several times may help too. 1. Slope is change in y divided by (over) change in x. The y value is the second value in each ordered pair; the x value is the first. If you had two points (a,b) and (c,d) you would form the fraction to find the slope: (d-b)/(c-a). However in this case, you are dividing by zero, which is illegal in math. Draw a simple little graph. It's a vertical line, which has infinite slope! 2. Just substitute (-2) in place of x in the right hand side of the equation and evaluate. You would have 5 times (-2) to the second power, minus 3 times -2, plus 1. Remember in evaluating to do powers first (-2) to the second power; then do all multiplications (5 times that result, 3 times -2); last do all additions and subtractions. 3. This means you solve for y. Since the y "term" has a coeffecient of a negative number, I would get the y "term" all alone on the right first and transfer everything else to the left hand side by whatever method you've been taught (transposition, adding the same thing to both sides etc.) This gives you 4x = 6y - 30. Then "get rid of" the -30 by adding 30 to both sides, and you have 4x + 30 = 6y. (or you can change it to 6y = 4x + 30. Then to solve for y, you have to divide both sides by 6. Remember BOTH terms have to be divided by 6 on the right. (Distributive law) So this gives you y = f(x) = 4x/6 + 30/6. This can be simplified to f(x) = 2x/3 + 5 or (2/3)x + 5. 4. I'd recommend that you draw a simple graph with these 2 points on it. Can you see that the line formed always has y = to -7? That's the equation! 5. I'd use the "pattern" or formula of y = mx + b where m is the slope (which is handily given to you). This brings us to the partial answer of y = -4x + b. Now we have to find out what b is. (b stands for the y-intercept, meaning the point at which the graph crosses the y axis. For example, if a line crossed the y axis at the point (0,2), the y-intercept would be 2.) To find b, you put in the x and y values you have for the known point. So solve the equation 3 = (-4)(-2) + b for b. Suppose you get -5 for b. Then the answer would be y = -4x + (-5), or more plainly, y = -4x -5. 6. Use slope = (change in y) divided by (change in x), like I first mentioned in #1. Then draw a simple graph. Something that looks like level ground should be a slope of zero, don't you think? 7. Slope here means to solve for y, and afterward, see what coefficient x has. Remember y = mx + b? So 5y = -2x + 10; y = (-2/5)x + 10/5 or y = (-2/5)x + 2. The slope is -2/5. The y intercept is the value of y when x is zero, or 2. 8. Perpendicular lines have slopes which are negative reciprocals of one another. You have to use y = mx + b to see that the 4 choices have slopes of 5/9, 6, -1/6, and 1/6, respectively. Which two have opposite signs and if you multiply the absolute values, you get 1 for the result? (This addresses the words "negative" and "reciprocals" directly. You could also say that the product of the slopes of 2 perpendicular lines is -1.) 9. Whew! Did you try graphing? That is a quick way if they're plainly parallel. What you're supposed to do is use the formula (change in y) divided by (change in x) in each. (Parallel lines have the same slope).
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