Question

solve 7 x + 10 by 5 x + 10 is 9 by 7​

Answer 1

Answer:

$\large\boxed{x=5}$

Step-by-step explanation:

$\textnormal{To solve this problem, first you have to find the value of x. Identify the variable.}$$\textnormal{Rewrite the original problem down equation.}$$\textnormal{Next, you substitute the value for the variable. Then, simplify and solve}$.

$\large\textnormal{First, you'd apply by the fraction of cross multiply.}$

$\displaystyle \frac{a}{b}=\frac{c}{d}=\textnormal{next}=a*d=b*c$

$\textnormal{Expand to solve with distributive property.}$

$\displaystyle (7x+10)*7=49x+70$

$\displaystyle (5x+10)*9=45x+90$

$\displaystyle 49x+70=45x+90$

$\large\textnormal{Next, subtract 70 from both sides.}$

$\displaystyle 49x+70-70=45x+90-70$

$\large\textnormal{Solve.}$

$\displaystyle 90-70=20$

$\displaystyle 49x=45x+20$

$\large\textnormal{Then, subtract 45x from both sides. }$

$\displaystyle 49x-45x=45x+20-45x$

$\large\textnormal{Solve.}$

$\displaystyle 49x-45x=4x$

$\displaystyle 20-45x=20$

$\displaystyle 4x=20$

$\large\textnormal{Divide by 4 from both sides. }$

$\displaystyle \frac{4x}{4}=\frac{20}{4}$

$\large\textnormal{Solve.}$

$\displaystyle 20\div4=\boxed{5}$

$\large\boxed{x=5}$

$\large\boxed{\textnormal{Therefore, the correct answer is \boxed{x=5}}}.$