Question

Use a graphing tool to solve the system.

3x-8y=29
3x+y=-2

Which ordered pair is the best estimate for the solution to the system?

A (0.75, -2.25)
B.(0, -3.75)
C.(0.5,-3.5)
D.(0,-2)

PLEASE HELP!! I am so lost...

Answer 1

y=-3x-2
3x-8(-3x-2)=29
3x+24x+16=29
27x=12
x=4/9
y=-4/3-2
y=-3 1/3
The closest approximation algebraically is (.5,-3.5)

Answer 2

Answer: C. ( 0. 5, -3. 5)

Explanation:

3x - 8y = 29 ---------(1)

3x + y = -2 ------------(2)

subtract (2) from equation (1)

-9y = 31

Divide bothside by -9

-9y / -9 = 31/ -9

y = -3. 4

substituting y= -3. 4 in equation (2)

3x + y = -2

3x + (-3. 4) = -2

3x - 3. 4 = -2

add 3. 4 to bothside of the equation

3x - 3. 4 + 3. 4 = -2 + 3. 4

3x = 1. 4

Divide bothside by 3

3x / 3 = 1. 4 / 3

x = 0. 5