Answer:
Step 3 they took the square root incorrectly
Step-by-step explanation:
5 ( x-2)^2 +6 = 86
Subtract 6 from each side
5 ( x-2)^2 +6 -6= 86-6
5 ( x-2)^2 = 80
Divide each side by 5
5 ( x-2)^2 /5 = 80/5
(x-2)^2 = 16
Take the square root of each side
sqrt((x-2)^2) = ±sqrt(16)
x-2 = ±4
Quantity of gasoline needed by a car to run 800 miles = 30 gallons
Quantity of gasoline needed by a car to run 1 mile =
= 30 ÷ 800
= 0.0375 gallons
So , to run 1 mile a car would need = 0.0375 gallons of oil
To run 700 miles the quantity of gasoline needed =
= 700 × 0.0375
= 26.25 gallons of gasoline
Therefore , a car will use 26.25 gallons of gasoline on a trip of 700 miles .
B. End of the reconstruction.
Y = -x + 4.....so sub in -x + 4 in for y in the other equation
x + 2y = -8
x + 2(-x + 4) = -8
x - 2x + 8 = -8
x - 2x = -8 - 8
-x = -16
x = 16
y = -x + 4
y = -16 + 4
y = - 12
one solution (16,-12)
