PRECALC AB
1 answer:
You might be interested in
4x - 2y ≤ 6 <em>subtract 4x from both sides</em>
-2y ≤ -4x + 6 <em>change the signs</em>
2y ≥ 4x - 6 <em>divide both sides by 2</em>
<h3>y ≥ 2x - 3</h3>y = 2x - 3 - it's a linear function. We need only two points to plot the graph.
Choose any two values of x and calculate the values of y:
for x = 0 → y = 2(0) - 3 = 0 - 3 = -3 → (0, -3)
for x = 2 → y = 2(2) - 3 = 4 - 3 = 1 → (2, 1)
--------------------------------------------------------------------------
<, > - dotted line
≤, ≥ - solid line
<, ≤ - shaded to left
>, ≥ - shaded to right
okay well for a) the line is perpendicular meaning that it need to go the opposite way of 2/3x+6 so in the new equation would have a negative value times x. also when you are trying to find a perpendicular line i believe you use the inverse of the slope meaning that you would have -3/2 time x. Then you know that the line goes through (-6,4) so you just replace x with -6, add a varible (for example n) and then set the equation equal to 4 since 4 should be the y value that you get when you plug in 4. so it should look like
(-3/2)-6+n=4 you're doing this so that you can figure out the x intercept. Move the n to the right and subtract 4 from both sides, and then solve the numbers on the left. (-3/2)-6 =9 and then 9-4=5 so the y intercept you get is five. then the new eqaution you shoud have is (-3/2)x-5=y
b.) well the x values are both positive meaning that you subtract so there is a distance of 2 units between then and the y values have a negative number and a positive number meaning you add so there is a distance of 5. The slope should be rise over run so the slope is 5/2 and then you can plug in a value of x to find the y intercept. lets use (6,-3) so
(5/2)6+n=-3. isolate the variable and tadaa you get a y intercept of -18. so the equation for the second one is (5/2)x-18=y
