Answer:
20
Step-by-step explanation:
Let's start by rewriting the second equation in terms of "x":

Subtract y from both sides:

Now, substitute "5-y" for "x" in the first equation:

Note that:


Cancel out like terms:

Subtract 25 from both sides:

Divide both sides by -10

Now, substitute this value back into either of the equations to solve for x.

Add 15/2 to both sides:

Now, find the difference:

If it is exactly 90 degrees you are looking for, your answer would be, 3:0:0. Which is 3:00.
Answer:

Step-by-step explanation:
The given rational expression is:

We can use concept of Partial Fractions to solve this problem. Let,

Multiplying both sides by (x - 1)(x - 5), we get:

Substituting x = 5, we get:

Substituting x = 1, we get:

Substituting the value of A and B, back in the original equation, we get:

800 is 10 times as much as 80
Use the formula for the sum of a geometric sequence:
Sum = (a(r^n - 1))/(r - 1)
where a is the first term, -3
r is the common ratio, -2
and n is the number of terms
Thus,
Sum = ((-3)((-2)^10 - 1))/(-2-1) = 1023