5
y = 3x 3x + 4y = 30 3x + 4(3x) = 30 3x + 12x = 30 15x = 30 x = 2 y = 3x y = 3(2) y = 6 (2, 6)
A pair of simultaneous eq;ns. 3x + y = 4 x + y = 0 Subtract the two eq'ns. This will eliminate 'y' 2x = 4 x = 2 Substitute this value of 'x' into either eq'n for 'y' 2 + y = 0 y = -2 or 3)2) + y = 4 6 + y = 4 y = 4 - 6 y = -2 ( again) . So the answer is ( x,y) = ( 2, -2).
3x + 2 = Y
-1
Their graphs are.
y = 2 sin 3x y' = 2(sin 3x)'(3x)' y' = 2(cos 3x)(3) y' = 6 cos 3x
1) y - 7y = 36 -6y = 36 y = -6 We know that, y = 3x -6 = 3x x= -2 Conclusion, y= -6, x = -2
1
1
3x - y = -1 x = -2 3(-2) -y = -1 -6 - y = -1 -y = 5 y = -5
y = 3x + 1 y = 3x + 2 y = 3x + 3 y = 3x
Y=2xx+y=3x+(2x)=33x=3x=1y=2x y=2*1y=2