5x^2 -15x-140
5(x² -(3x) -28)
5(x² +(4x-7x)-28)
5(x(x+4) -7(x+4)
5(x-7)*(x-4)
Answer is x = 7
if u plug in 7 in the second expression, we can get 7 - y = 4, isolate y and then we get 3.
Now, plug in 7 in the first equation to get 2(7) + y = 17. that results to 14 + y = 17. isolate y again and then thats also 3.
so:
x = 7
y = 3
For direct variation, y = kx
8 = -4k
k = 8/-4 = -2
Therefore, required equation is y = -2x
when x = 7, y = -2(7) = -14
I got the answer as to be C
Answer:
3 hours times 6.80= 20.40
2 hours times 6.20= 12.40
20.40 + 12.40 = 32.80
32.80 ÷ the 5 hours= $6.56 per hour average
