solve using substitution 7 2x5y 1 3x7y 2 12 57 23 Solution

solve using substitution

Solution

2X+5Y = 1

3X+7Y = 2

NOW USING 1ST

2X+5Y = 1

2X = 1-5Y

X = (1-5Y)/2 -------------A

PUT VALUE OF X IN 2ND EQUATION

3(1-5Y)/2 +7Y = 2

3/2 - 15Y/2 +7Y = 2

-1/2Y = 2-3/2

Y = -1

HENCE X = (1+5)/2 = 3