2x²+7x+9x-2=38 2x²+16x-40=0 2(x²+8x-20)=0 2(x+10)(x-2)=0 x=-10 or x=2 if we let x=-10 we get negative lengths for some of the segments which is not allowed so discard it. for x=2,
When figuring this out you can just plug in your answers if you want to take it the easier way by just putting in the 35 in places of x and multiplying 0.1 times 35 gets you 3.5 so 3.5 minus 2.5 is 1