#### Answer

42875

#### Work Step by Step

$(4y-5z)^3$ $\longrightarrow$ substitute
=$(4(-5)-5(3))^3$ $\longrightarrow$ solve operations in parenthesis; multiply
=$(-20-15)^3$ $\longrightarrow$ solve operations in parenthesis; multiply
=$(-35)^3$ $\longrightarrow$ solve exponent
=$42875$