Solve the simultaneous equations: y = 4x^2 - 9x - 1 and y = 5 - 4x
Subtract the second equation from the first, giving you: 4x^2 -5x -6
Factorise the quadratic: (4x + 3)(x - 2)
x = -0.75
x= 2
Now substitute these values into one of the equations (or both, just to double-check) and get your y value.
y = 5 - 4(-0.75)
y = 8
y = 5 - 4(2)
y = -3
Answer:
x = 2 y = -3
x= -0.75 y= 8
DA
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