A + C
(-5, -7) is 7 units to the left of point H
(-7, 7) is more than 7 units up and left of point H
the x axis is at (infinity, 0), being only 7 points up from point H
You can first take out an x^2 from each number , 3x^6 - 39x^4 + 108x^2 = x^2 ( 3x^4 - 39x^2 + 108) Then just factor and solve for the zero's of the equation
<span>6 bags of plaster do 33m2
5 bags .........................?
33 * 5 / 6 = 27.5
answer: 27.5</span><span>m2</span>