X + y = 13
x - y = 5
x = (13 - y)
(13-y) - y = 5
13 - 2y = 5
-2y = -8
y = 4
x - 4 = 5
x = 9
x=9, y = 4
Answer: Choice D) 
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Work Shown:
Point A starts at (-2,3) and moves to (2,5) after applying the translation rule of "shift 4 to the right, 2 up".
Use the distance formula to find the distance from (-2,3) to (2,5)

A=-2;b=9;c=9;
delta=b^2-4*a*c
root1=(-b+(delta^(0.5)))/(2*a)
<span>root2=(-b-(delta^(0.5)))/(2*a)
delta =153
root1 = -0.8423
root2 =<span> 5.3423
Correct Answer is D</span></span>
You could first solve for y, assuming x is 0, and y = 6. Then solve for x, and that means y = 4.
So basically it takes 10 people to paint a whole building. Forget about the 5 days. That's just there to confuse you. You have to first find out how much of a building can one person paint so, 1/10. So that means that 7 people can paint 7/10 of a building in 5 days