2y = -10y = -58 - 2x - 2(-5) = -108 - 2x + 10 = -10-2x = -10 - 182x = 28x = 14Check:2y = 8 - 2x - 2y = -102(-5) = 8 - 2(14) - 2(-5) = -10-10 = 8 - 28 + 10 = -10-10 = -20 + 10 = -10-10 = -10 = -10
One solution 2x+y =5 x+2y=4 multiply 1st eq by 2 rhen subtract: 4x+2y = 10 x + 2y = 4 3x = 6 x = 2 plug x into any of the above two equations and solve y = 1
y = 0 and x = 8.
Simultaneous suggests at least two equations.
16x - 2y = 74 (Eq 1) 2x - 2y = 4 (Eq 2) from Eq 2, 2y = 2x - 4 Substitute in Eq 1 16x - (2x - 4) =74 ie 16x - 2x + 4 = 74 ie 14x = 70 ie x = 5 2y = 2x - 4 = 10 - 4 = 6 y =3 Check 16 x 5 - 2 x 3 = 80 - 6 = 84 QED
The solution is:- x = 0 and y = 5
2y = -10y = -58 - 2x - 2(-5) = -108 - 2x + 10 = -10-2x = -10 - 182x = 28x = 14Check:2y = 8 - 2x - 2y = -102(-5) = 8 - 2(14) - 2(-5) = -10-10 = 8 - 28 + 10 = -10-10 = -20 + 10 = -10-10 = -10 = -10
Divide both sides by 2: 2x = 10 - 2y __ __ ___ 2 2 2 x = 5 - y
The two equations are linear.
4x + 2y = 20 2y = -4x + 20 y = -2x + 10.......but you may also write it as y = 10 - 2x.
(12, 1)
1 solution
10-2y
-2x=2y+5 +2x -2y -2y=2x+5 /-2 y=-1/1+2.5
4x-2y = 10 -2y = -4x+10 y = 2x-5 which is now in slope-intercept form
(4, -1)
x = 3 and y = 2