Answer: x = 10, y = -2 ;→ Write as: (10, -2) . _______________________________________________ Explanation: _______________________________________________ Given: _______________________________________________ x = 10 ;
3x + 5y = 20 ; _______________________________________________ → Plug in "10" for the value of "x" in the second equation: _______________________________________________ 3*(10) + 5y = 20 ; Solve for "y" ; _______________________________________________ ↔ 5y + 3*(10) = 20 ;
5y + 30 = 20 ; ________________________________________________ Subtract "30" from EACH side of the equation: ________________________________________________ 5y + 30 − 30 = 20 <span>− 30 ; </span> 5y = - 10 ; __________________________________________________ → Divide EACH SIDE of the equation by "5" ; to isolate "y" on one side of the equation; and to solve for "y" ; ___________________________________________________ 5y / 5 = - 10 / 5 ; ___________________________________________________ y = - 2;
And we are given: x = 10 ; _________________________________________________ → Let us check our answer, by substituting "10" for "x"; and "-2" for "y" ; in the second equation given; to see if the equation holds true: __________________________________________________ Given: ... 3x + 5y = 20 ;