×

# SAT Linear Functions

In the $$xy$$-plane, line $$m$$ is parallel to the $$y$$-axis and passes through the point $$(-4, 5).$$ Which of the following is an equation for line $$m$$?

(A) $$\ \ x=-4$$
(B) $$\ \ y=5$$
(C) $$\ \ y=-4x+5$$
(D) $$\ \ 5y=-4x$$
(E) $$\ \ y+5=x-4$$

Line $$l$$ has the equation $$y=-7x+70.$$ If it crosses the $$x-$$axis at the point $$(a+1, b-1),$$ what is the value of $$a$$?

(A) $$\ \ 0$$
(B) $$\ \ 9$$
(C) $$\ \ 10$$
(D) $$\ \ 70$$
(E) $$\ \ 71$$

$$\$$
The hypotenuse in the right triangle above has a slope $$m=28$$. If $$x$$ is $$5.25$$, what is $$y$$?

(A) $$\ \ \frac{3}{16}$$
(B) $$\ \ 5$$
(C) $$\ \ 5.25$$
(D) $$\ \ 140$$
(E) $$\ \ 147$$

In the $$xy$$-plane, line $$m$$ contains the points $$(0, 6)$$ and $$(2, 14),$$ and line $$n$$ contains the points $$(k, 3)$$ and $$(37, 8).$$ If line $$m$$ is perpendicular to line $$n,$$ what is the value of $$k?$$

(A) $$\ \ 0$$
(B) $$\ \ 4$$
(C) $$\ \ 17$$
(D) $$\ \ 34$$
(E) $$\ \ 57$$

$$\ \$$
The coordinates of point $$B$$ in the figure above are $$(h,k),$$ where $$20|h|=|k|.$$ Which of the following is the slope of $$\overline{AB}$$?

(A) $$\ \ 20$$

(B) $$\ \ \frac{21}{20}$$

(C) $$\ \ \frac{1}{20}$$

(D) $$\ \ -\frac{1}{20}$$

(E) $$\ \ -20$$

×