Question

The value of z when 4(.5z-10)=10z+4

Answer 1

Start by expanding the left hand side:

$4 \times 0.5 z + 4 \times (-10) = 10z+4$

which leads to

$2z -40 = 10z+4$

Now we want to move all terms involving the variable to the left hand side, and all constant terms on the right hand side:

$2z-10z = 4+40$

Simplify both sides by summing like terms:

$-8z = 44$

Divide both sides by -8 to solve for x:

$z = \cfrac{44}{-8} = -\cfrac{22}{4} = -\cfrac{11}{2} = -5.5$