
because when you differentiate, only the constant of the x remains (which is m in this case), and c being another constant independent of x, is 0 when differentiated. hence, since dy/dx is the gradient of the line, m is therefore the gradient
£4/8 = £0.50 ..........................
I think it’s seventy five
80
<span>Using the rule of 3, 60x100% =6000(obviously) and 6000/75 = 80</span>