Multiply the bracket by 5
I used PEMDAS
P= parenthesis
E= exponents
M=multiplication
D= division
A= addition
S= subtraction
7r+2= 5(r-4)
7r+2= 5r-20
Move 5r to the left hand side . Positive 5r changes to negative 5r
7r-5r+2= 5r-5r-20
2r+2=- 20
2r+2-2= -20-2
Move positive 2 to the right hand side. Changes to negative -2
2r+2-2= -20-2
2r= -22
Divide by 2 for 2r and -22
2r/2= -22/2
r= -11
Answer is r= -11
Your answer is 21 for this one.
Answer:
The first step is to replace the y in y-x=15 with 7x (we can do this because the first equation tells us that they're equal)
solve and get
(2.5,17.5)
or x= 2.5 y=17.5
Step-by-step explanation:
The first step is to recognize that y=7x which means that we can just replace the y in the second equation with 7x
7x-x=15
6x=15
x=2.5
Then we can solve for y
y=7(2.5)
y=17.5