Torrance is buying presents
for members of his family. He wants to
spend $10 less on his brother than he
spends on his sister, and six dollars
more than twice the amount he spends
on his sister on his mother. If Torrance
has $100 to spend, how much does he
intend to spend on his brother?

Respuesta :

Step-by-step explanation:

x = spending on brother

y = spending on sister

z = spending on mother

x + y + z = 100

x = y - 10

z = 2y + 6

now we use the second and third equations in the first :

y - 10 + y + 2y + 6 = 100

4y - 4 = 100

y - 1 = 25

y = $26

x = y - 10 = 26 - 10 = $16

z = 2y + 6 = 2×26 + 6 = 52 + 6 = $58

so he plans to spend $16 on his brother.