x + 7y = 33 (1) --> x = 33 - 7y (1a) 3x - 2y = 7 (2) To solve the simultaneous equations, starts by substituting the value for x found in (1a) into (2): 3(33 - 7y) - 2y = 7 99 - 21y - 2y = 7 -23y = -92 y = 4 Now substitute this value for y into (1a) and solve for x: x = 33 - 7(4) x = 33 - 28 x = 5 Therefore these equations have the solution x = 5, y = 4
x + 7y = 33 multiply through by 3: 3x + 21y = 99 Subtract the second equation from the above equation: 23y = 92 So y = 4 Substituting this value of y in the first equation, x + 28 = 33 ie x = 5 The solution is (x,y) = (5,4)
x=4 y=5 9x+7y=?? Replace: 9(4)+7(5)= 71
y = -1 and x = -3
if: 2x + 6 = -6 then: 2x = -12 x = -6 if: 5x + 7y = 1 then: 5(-6) + 7y = 1 7y = 31 y = 31/7
x = 5 and y = 4
The ordered pair is (5, 4).
x + 7y = 33 (1) --> x = 33 - 7y (1a) 3x - 2y = 7 (2) To solve the simultaneous equations, starts by substituting the value for x found in (1a) into (2): 3(33 - 7y) - 2y = 7 99 - 21y - 2y = 7 -23y = -92 y = 4 Now substitute this value for y into (1a) and solve for x: x = 33 - 7(4) x = 33 - 28 x = 5 Therefore these equations have the solution x = 5, y = 4
x + 7y = 33 multiply through by 3: 3x + 21y = 99 Subtract the second equation from the above equation: 23y = 92 So y = 4 Substituting this value of y in the first equation, x + 28 = 33 ie x = 5 The solution is (x,y) = (5,4)
x + 7y = 7 ⇒ 7y = -x + 7 ⇒ y = -x/7 + 1 ⇒ y intercept is 1.
x+7y=16 ---------------------------1 3x- 7y=4 ---------------------------2 ------------------------------------------------------------------------------------------------------------------ 1+2 x+7y=16 3x-7y=4 4x=20 x=5 substitute x = 5 in x+7y=16 (5)+7y=16 7y=11 y=11/7
4
53
99
x=4 y=5 9x+7y=?? Replace: 9(4)+7(5)= 71
y = -1 and x = -3
(5, 1)