Answer:
(c)
Step-by-step explanation:
Using the cosine ratio in the right triangle
cos42° =
= 
Multiply both sides by 12
12 × cos42° = x, hence
x ≈ 8.9 → (c)
So when you are trying to find the solution to the system of equations make sure that you have it where y= -4/5x-6 and y= -30 are written like this:
-30=-4/5x-6
And then solve for x:
Add 6 on both sides.
-24=-4/5x
Then multiply by the reciprocal of -4/5.
-5/4*-24=-5/4*-4/5x
x=30
But then you are gonna want to plug 30 in for x in y=-4/5x-6 to make sure that it is the same as y=-30.
X = number of days it would take Kate to paint the house by herself. .
<span>x+5 = number of days it would take Jean to paint the house by herself.</span>
<span>Together, they paint the house in 6 days: </span>
<span>1/x + 1/(x+5) = 1/6 </span>
<span>Multiply both sides by 6x(x+5) </span>
<span>6(x+5) + 6x = x(x+5) </span>
<span>12x + 30 = x^2 + 5x </span>
<span>x^2 − 7x − 30 = 0
</span>therefore the answer is A.
Graph b has a correlation closest to -0.95