Question

One number is 7 less than 3 times the second number. Their sum is 29. Find the numbers.

Let x be the second number.

Answer 1

the first number is 20, second is 9

Explanation:

y=3x-7

y+x=29

rearrange the first equation

y-3x=-7

and

y+x=29

solving the simultaneous equation:

y-3x=-7

-

y+x=29

= -4x=-36

divide both sides by -4

x = 9

now substitute the x value into the equation: y+x=29

= y + 9 = 29

y = 20