Answer:
y = - x² - 4x - 9
Step-by-step explanation:
Given
y = - (x + 2)² - 5 ← expand (x + 2)² using FOIL
= - (x² + 4x + 4) - 5 ← distribute parenthesis by - 1
= - x² - 4x - 4 - 5 ← collect like terms
= - x² - 4x - 9 ← in standard form
Option A
The solution is 
<em><u>Solution:</u></em>
<em><u>Given system of equations are:</u></em>
3x + 6y = 1 ------ eqn 1
x - 4y = 1 ------ eqn 2
We have to find solution to system of equations
We can use substitution method
From eqn 2,
x = 1 + 4y -------- eqn 3
Substitute eqn 3 in eqn 1
3(1 + 4y) + 6y = 1
3 + 12y + 6y = 1
18y = 1 - 3
18y = -2
Divide both sides by 18
Substitute the above value of y in eqn 3
Thus solution is
Answer:
y= 84
Step-by-step explanation:
y = kx
where k is the constant
k = y/x = 91/13 = 7
the value of Y when x= 12
y = kx =7(12)
y =84
9. D because it fits the description when it is graphed.
11. D because it has the correct vertex, which is (1.5, 4.75).
12. f(x)=-4(x-2)²+16 works with the table and provided graph!
13. 0 isn't a zero for f(x), so B is correct (the zeros are 1/2 and 4).
14. The width is about 3.831.
15. The answer is B because the equation for a parabola in this form is:
f(x) = (x - r₁)(x - r₂)
Every one of these except for 15 was solved using desmos, a graphing calculator.
Hope this helps!
