Answer:
The answer is D
Step-by-step explanation:
(12 + 6) x ( 11 - 7) = 72
18 x 4 = 72
72 = 72
Step-by-step explanation:
The discriminant of the quadratic equation
:

If Δ < 0, then the equation has two complex roots 
If Δ = 0, then the equation has one repeated root ![x=\dfrac{-b}{2a}[/tex If Δ > 0, then the equation has two discint roots [tex]x=\dfrac{-b\pm\sqrt\Delta}{2a}](https://tex.z-dn.net/?f=x%3D%5Cdfrac%7B-b%7D%7B2a%7D%5B%2Ftex%20%3C%2Fp%3E%3Cp%3EIf%20%CE%94%20%3E%200%2C%20then%20the%20equation%20has%20two%20discint%20roots%20%5Btex%5Dx%3D%5Cdfrac%7B-b%5Cpm%5Csqrt%5CDelta%7D%7B2a%7D)




The equation is
9 × g = 162
9g = 162
Solving foe Gall's age,
9g = 162
g = 162 ÷ 9
g = 18
Distance÷time
440÷8= 55
Therefore he needs to drive at the speed of 55 miles/hour
Answer:
can u explain more
Step-by-step explanation: