Answer:
Step-by-step explanation:
4x + 5y = 6 -----------(I)
y = -5x - 3 --------(II)
Substitute y = -5x - 3 in equation (I)
4x + 5 (-5x - 3) = 6
4x - 25x - 15 = 6
Add 15 to both sides
4x - 25x = 6 + 15
Combine like terms
-21x = 21
Divide both sides by (-21)
x = 21/(-21)
x = -1
Substitute x = - in equation (II)
y = -5(-1) - 3
= 5 - 3
y = 2
Solutions (-1 , 2)
2) -3x + y = 2-------------(I)
-x + y - 4 = 0
y = 4 + x ------------(II)
Substitute y = x + 4 in equation (I)
-3x + x + 4 = 2
-3x + x = 2 - 4
Combine like terms
-2x = -2
Divide both sides by (-2)
x = (-2)/(-2)
x = 1
Substitute x = 1 i n equation (II)
y = 4 + 1
y = 5
Solution (1,5)
3) 5x + 2y = 5 ------------(I)
y = -2x + 3 ------------(II)
Substitute y = -2x + 3 in equation (I)
5x + 2*(-2x + 3) = 5
5x - 4x + 6 = 5
5x - 4x = 5 - 6
Combine like terms
x = -1
Substitute x = -1 in equation (II)
y = (-2)*(-1) + 3
= 2 + 3
y = 5
Solution: ( -1 , 5)
