Answer:
His sister will be 13 yrs old
Step-by-step explanation:
twice as many as 5 is 10. so the sister is five yrs older than the brother. if you add 5 to 8, you get 13.
<u>5 + 8 = 13</u>
-3y = 12 1) divide -3 on both sides
y = -4
Hope this helps!!!
Answer:
x=10, y=-1
Step-by-step explanation:
The coefficients of y are opposites, so the y-variable can be eliminated by adding the two equations.
... (x -y) +(2x +y) = (11) +(19)
... 3x = 30 . . . . . simplify
... x = 10 . . . . . . .divide by the coefficient of x
Use either equation to find y. We can use the first one, for example:
... 10 -y = 11
... -1 = y . . . . . add y-11
The solution is (x, y) = (10, -1).
Multiply 12 x 12 which is 144. And then you divide that by 6 and you get 24
