Answer
Step-by-step explanation:
[tex] \sf{ \frac{40}{x + 1} = \frac{15}{6} }[/tex]
Do cross multiplication
[tex] \dashrightarrow{ \sf{15(x + 1) = 40 \times 6}}[/tex]
Distribute 15 through the parentheses
[tex] \dashrightarrow \sf \: 15x + 15 = 40 \times 6[/tex]
Multiply the numbers : 40 and 6
[tex] \dashrightarrow{ \sf{15x + 15 = 240}}[/tex]
Move 15 to right hand side and change it's sign
[tex] \dashrightarrow{ \sf{15x = 240 - 15}}[/tex]
Subtract 15 from 240
[tex] \dashrightarrow \: \sf{15x = 225}[/tex]
Divide both sides by 15
[tex] \dashrightarrow{ \sf{ \frac{15x}{15} = \frac{225}{15} }}[/tex]
Calculate
[tex] \dashrightarrow{ \sf{x = 15}}[/tex]
Hope I helped!
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