Respuesta :
Answer:
x=15
Step-by-step explanation:
This is a simultaneous equation
2x-3y=45 ------------------------------ equation i
x+y=10 -------------------------------equation ii
from equation ii
x+y=10
make x the subject of the matter
we have,
x=10-y
in equation i
substitute x for 10-y
2x-3y=45----------------------i
since x=10-y
we have,
2(10-y) - 3y=45
20-2y=3y=45
collect like terms
-2y-3y=45-20
-5y=25
divide both sides by -5
we have y=-5
substitute y for-5 in equation i
x+y=10
x+-5=10
collect like terms
x=10+5
x=15
therefore
x=15
Answer:
x = 15
Step-by-step explanation:
Use the second equation to write an expression for y:
y = 10 -x
Then, substitute this into the first equation and solve for x.
2x -3(10 -x) = 45
5x -30 = 45 . . . . . eliminate parentheses
x -6 = 9 . . . . . . . . .divide by 5
x = 15 . . . . . . . . . . .add 6