Question

PLEASE HELP!! MATH QUESTION!! 20 points!!

Answer 1

Answers
7, 11 are linear.
9 is a quadratic. y = 2x^2 - 3

Problem 11
First find the slope.  Use the first two points to do that.
y2 = 8
y1 = 6
x2 = - 3
x1 = - 1

Sub and solve
y = (y2 - y1) / (x2 - x1)
y = (8 - 6) / (-3 - - 1)
y = 2/- 2
y = - 1

Step 2
Find the y intercept
So far we have 
y = - x + b
x = 0
y = 5
5 = 0 *-1 + b
b = 5

Answer
 y = -x + 5

Problem 9
is the quadratic.

y = a*x^2 + b
when x = 0
y = - 3
y = ax^2 - 3  Now use any other point to solve for a.

Use (2,5)
5 = a(2)^2 - 3  Add 3 to both sides.
5 + 3 = a*4
8 = 4a    Divide by 4
8/4 = a
2 = a

check
Use (-1,1) to check
y = 2x^2 - 3
y = 2(-1)^2 - 3
y = 2*1 - 3
y = 2 - 3
y = - 1     Which is as it should be.

Problem 7
Is linear. Do the same way as 11. 
The graph is included below.

See if you can get the equation line.

You should get 
y = 2x - 4