Question

Few math questions.. I am really behind in math. (: thanks

Choose the equation of the horizontal line that passes through the point (1, −5).

y = −5
x = 1
y = 1
x = −5

Answer 1

If f(x) = 2x2 − 10, find f(5).

90
10
7.5
40

Answer 2

Choose the equation of the vertical line passing through the point (−4, 2).

y = −4
x = −4
y = 2
x = 2

Answer 3

y = x − 3
y = −x + 3
y = −x − 3
y = x + 3

Answer 4

methods:

1)From the drawing we notice that for any value of x , y = -5
2) equation of staight line y = mx + b

slope of horizontal line is 0 because dy/dx = -5 - (-5) / dx = -5 + 5/dx = 0

y = 0 * x + ( y-interception)
y = -5

Answer 5

let f(x) = x to find f(x) when x = 2
All you do is replacing each x with the given value , you can even re-write f(x) as y and you have the value of x given. ( let f(x) be y)
f( x= 2)= f(2) = 2 , y= x ? what's y ? 2 as x :

Answer 6

To find the equation you can use the slope equation y_2 - y_1/ x_2 - x_1

Answer 7

In both 1, 3

Answer 8

1. A horizontal line is represented by y = a number....so the first one is y = -5

Answer 9

vertical line passing through the point (−4, 2).
assume another point (x,y) which the line passes through.
slope of vertical line = undefined = 1/0
y -2 / x +4 = 1/0
x = -4

Answer 10

a vertical line is represented by x = a number....so 3 is x = -4

Answer 11

Last one has a positive slope so y = mx + b ( m > 0) and the interception is 3
so y = x + 3

Answer 12

if f(x) = 2x^2 - 10....find f(5)
sub in 5 for x
f(5) = 2(5^2) - 10
f(5) = 2(25) - 10
f(5) = 50 - 10
f(5) = 40

Answer 13

@TrojanPoem @texaschic101 thank you.. sorry for the late reply.

Answer 14

its all good :)

Answer 15

Any time.