Answer:
5/2
Step-by-step explanation:
We are looking for p+q+r.
We are given:
p+q =4 Equation 1.
q+r=-2 Equation 2.
p +r=3. Equation 3.
I'm going to solve the first equation for p giving me p=4-q.
I'm going to solve the second equation for r giving me r=-2-q.
I'm going to plug this into the third equation.
p +r=3
(4-q)+(-2-q)=3
4-q+-2-q=3
Combine like terms:
2-2q=3
Subtract 2 on both sides:
-2q=1
Divide both sides by -2:
q=-1/2.
Plug into the first equation to find p now.
First equation is p+q=4 with q=-1/2.
p+q=4
p+(-1/2)=4
Add 1/2 on both sides
p=4+1/2
p=9/2.
Let's find r now.
Using the second equation with p=9/2 and/or q=-1/2 we have:
q+r=-2
-1/2+r=-2
Add 1/2 on both sides
r=-2+1/2
r=-3/2
So what is p+q+r?
Let's plug in our p,q, and r and find out!
p+q+r
9/2+-1/2+-3/2
9/2-4/2
5/2
