Question

2x - 3y = 45 and x + y = 10 what is the x - value of the solution of the system

Answer 1

x = 15

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

Answer 2

x=15

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