d = 8c
d + c = 54
We can plug 8c into the value for d in the second equation to find the value of c.
8c + c = 54
Combine like terms.
9c = 54
Divide both sides by 9.
c = 6 (This is how much the cat weighs.)
Now we can plug this value in for c to find the value of d.
d + 6 = 54
Subtract 6 from both sides.
d = 48. (This is how much the dog weighs.)
We can plug these values into both of the original equations to verify.
d = 8c
48 = 8(6)
48 = 48 √ this is correct.
d + c = 54
48 + 6 = 54 √ this is also correct.