Answer:
A.
Step-by-step explanation:
1) to rewrite the given equation:
f(x)=2(x²+4x)-3; ⇔ f(x)=2(x²+4x+4)-3-8; ⇔ f(x)=2(x²+4x+4)-11; ⇔ f(x)=2(x+2)²-11;
2) the roots are:

3) finally, the correct answer is A.
Answer:
1 hour= 45 miles
1/2 hour=22.5 miles
3 hours= 135
Step-by-step explanation:
just work out one hour by halving 90 miles which is 45. Then work out the rest by halving again and multiplying by 3.
9514 1404 393
Answer:
D. y = -0.32x² -1.26x +15.81
Step-by-step explanation:
This is one of those multiple-choice questions where you only need a vague idea of what the answer is supposed to look like.
In this case the answer must be a quadratic equation with a negative leading coefficient. (The parabola opens downward.)
The only answer choice that is a 2nd degree polynomial with a negative leading coefficient is choice D.
__
A: linear equation
B: exponential equation
C: quadratic that opens upward (positive leading coefficient)
D: quadratic that opens downward -- the answer you're looking for
Circumference of circle = 11.27π ft
so,
C = 2πr
or, 11.27π = 2πr
or, 11.27π/2π = r
so, r = 5.635 ft
now,
diameter = 2r
= 2 x 5.635
= 11.27 ft