Question 60419

10x+2y=7 and
 y=5x+3
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y=5x+3

substitute the value y = 5x + 3 in the first equation

==>  10x + 2*(5x+3) = 7

10x + 2*5x + 2*3 = 7

10x + 10x + 6 = 7

20x+6 = 7

subtract 6 from both sides of the equation

==>   20x = 1

==>     x = 1/20

Now substitute the value, x = 1/20 in second equation(you can substitute the value of x in first equation also)

==> y = 5* 1/20 + 3

==> y = 4 + 3
==> y = 7

so the solution of the given equations are x = 1/20  and  y = 7
bye.