Question

One number is 7 more than another number. The sum of the numbers is 63. What are the numbers?
A. 10 and 7
B. 30 and 37
C. 28 and 35
D. 54 and 9

Answer 1

x = a number
y = the other number

y + 7 = x
x + y = 63
now sub y + 7 in for x in the 2nd equation

Answer 2

do you understand ?

Answer 3

so wait, i do y + 7 = 63 ?

Answer 4

no....sub in y + 7 in the 2nd equation....like this
x + y = 63
(y + 7) + y = 63

Answer 5

now combine like terms

Answer 6

okay, so them as a whole equation makes 35 and 28
if i just do the x+y=63
then (y+7) + y = 63

Answer 7

atleast thats what my calculator shows is 35 and 28

Answer 8

let me check
y + 7 + y = 63
2y + 7 = 63 (subtract 7 from each side)
2y = 63 - 7
2y = 56
y = 28

x + y = 63
x + 28 = 63
x = 63 - 28
x = 32

you got it :)

Answer 9

i know i could have just done that in the first place, but i needed to know the formula for it so when i go for my tests i have the formula!

thank you so much for the explanation!!

Answer 10

The hardest part about problems like this is the set up. Because if it is not set up correctly, it messes the whole problem up.
Glad to be of help :)