Answer:
25
Step-by-step explanation:
Eleana is 20 years old and her grandfather is 80 years old.
So first off, we want to make variables to represent Eleana and her grandfather.
Let x represent Eleana's age.
Since her grandfather is four times older than Eleana,
The expression should be 4x+x=100
Step One
Add the x's together and you get 5x=100.
Step Two
Divide both numbers by 5 to solve for x.
x=20
Step-by-step explanation:this is confusing for me oof
a = (r/x) -b
x = -14
r=x(a+b)
Divide each side by x
r/x = a+b
Subtract b
r/x -b = a
x/2=-7
Multiply each side by 2
x/2*2 = -7*2
just split the awnser
The percent markup is 62.5%
The work is provided in the image attached.
