Explanation:
Building proportional relationships
[tex]\sf \dfrac{XA}{XY} = \dfrac{XB}{XZ}[/tex]
21.
[tex]\sf \rightarrow \dfrac{5}{XY} = \dfrac{10}{18}[/tex]
[tex]\sf \rightarrow XY = \dfrac{5(18)}{10}[/tex]
[tex]\sf \rightarrow XY = 9[/tex]
Then find AY
[tex]\sf AY = XY - XA[/tex]
[tex]\sf AY = 9 - 5[/tex]
[tex]\sf AY = 4[/tex]
[tex]\hrulefill[/tex]
22.
[tex]\rightarrow \sf \dfrac{10}{25} = \dfrac{XB}{XB + 3}[/tex]
[tex]\rightarrow \sf 10(XB + 3) = 25XB[/tex]
[tex]\rightarrow \sf 10XB + 30 = 25XB[/tex]
[tex]\rightarrow \sf 25XB-10XB = 30[/tex]
[tex]\rightarrow \sf 15XB = 30[/tex]
[tex]\rightarrow \sf XB = 2[/tex]
Then find XZ
[tex]\sf XZ = XB + BZ[/tex]
[tex]\sf XZ = 2 + 3[/tex]
[tex]\sf XZ = 5[/tex]
[tex]\hrulefill[/tex]
23.
[tex]\sf \rightarrow \dfrac{4}{13} = \dfrac{XB}{26}[/tex]
[tex]\sf \rightarrow \dfrac{26(4)}{13} = XB[/tex]
[tex]\sf \rightarrow XB = 8[/tex]
