The given equation is

To solve for x, we have to subtract 8 to both sides

Now we need to get rid of -9 from the left side, and for that we do division


A circle, of radius r = radius of the sphere
you can think of it in terms of projection the plan projection of the sphere is a circle.
When solving system equations, we can use substitution method or elimination. Today I'm using substitution method.
First name the 2 equations.
3x + y = 3 (1)
x + y = 2 (2)
Now pick one equation and express one algebra in forms of the other.
From (2),
x = 2 - y (3)
Now substitute (3) into (1),
3(2-y) + y = 3
6 - 3y + y = 3
6 - 2y = 3
6 - 3 = 2y
y = 1.5
Now substitute y = 1.5 into (2)
x + 1. 5 = 2
x = 2 - 1.5
x = 0.5
Therefore the answer is x = 0.5 and y = 1.5
Set up an equation to solve.
$8.50x (since it is the rate of change) + $12 (flat fee) = total money earned (or y). In this case, we have the total, amount, and are looking for x. Plug $139.50 into the equation.
$8.50x + $12 = $139.50
Now, solve for x.
$8.50x + $12-12 = $139.50-12 > <em>$8.50x = $127.5</em>
$8.50/8.50x = $127.5/8.50 > <em>x = 15</em>
So, the correct answer is <u>D. Olivia babysat for 15 hours.</u>