Answer:
or 
Step-by-step explanation:
Substitution means plugging in one variable's value that consists of the opposite variable. Because
is already specified, you can plug it into the second equation's
value. After doing that, it looks like this:

Then you would distribute the
across the parentheses next to it, like this:

Then, add like terms, like this:

Then divide both side by
to isolate
.

Now, you can plug
(
) into either equation, but the first one seems simpler so you would pick that. It would look like this:

Solving would look like this:

So the answer is
or
.
Answer:
1 : 1
Step-by-step explanation:
When a circle is inscribed in a cylinder, the height of the cylinder is equal to the diameter of the sphere and the radius of the cylinder is same as that of the sphere.
Let the radius of sphere is r.
height of cylinder, h = 2r
radius of cylinder = r
Surface area of sphere, A = 4πr²
lateral surface area of cylinder, A' = 2 πrh
A' = 2πr x 2r = 4πr²
The ratio of surface area of sphere to the lateral surface area of cylinder is 1 : 1.
I believe the answers are c and d
Answer:
The expressions for the payment made to Mary are,
(Monday) 90 = 15m + b
(Tuesday) 62 = 8m + b
where m and b are the fee per student and the base fee, respectively. Solving for m and b, the values are 4 and 30.
The equation that represents Mary's earning is
y = 4x + 30
For 20 students,
y = 4(20) + 30 = 110
For Lisa's earnings,
y = 8x + 15
Substituting 20,
y =8(20) + 15 = 175
Thus, Lisa would earn more than Mary by $65.
(Btw this is not my work, I got it from someone else on brainly and wanted to help lol)
Distinct prime factors are factors that can not be reduced any further.... Such factors are like 3,5, and 7.