Prealgebra (7th Edition)

Let $x$ be life expectancy for a chimp. Life expectancy for an elephant is $x+24$. $x+x+24=130$ $\longrightarrow$combine like terms $2x+24=130$ $\longrightarrow$addition property $2x+24-24=130-24$ $\longrightarrow$simplify $2x=106$ $\longrightarrow$multiplication property $2x\div2=106\div2$ $\longrightarrow$simplify $x=53$ $x+24=53+24=77$