Question

calcule as expressões algebricas -yb²+yb²-7yb²+15yb²

Answer 1

A resolução é:

$-yb^2+yb^2-7yb^2+15yb^2=\text{ (Colocando o yb}^2\text{em evidencia)}\\yb^2\cdot \left(-1+1-7+15\right)=\\yb^2\cdot \left(-7+15\right)=\\yb^2\cdot 8=\\\boxed{\bold{8yb^2}}$