Question

slove x-4/7 - x+4/5 = x+3/7​

Answer 1

Step-by-step explanation:

Required Answer

$\sf {\dfrac{x-4}{7}}-{\dfrac {x+4}{5}}={\dfrac {x+3}{7}}$

${:}\longrightarrow$$\sf {\dfrac {5 (x-4)-7 (x+4)}{35}}={\dfrac {x+3}{7}}$

${:}\longrightarrow$$\sf {\dfrac {5x-20-7x+28}{35}}={\dfrac {x+3}{7}}$

${:}\longrightarrow$$\sf {\dfrac {5x-7x-20+28}{35}}={\dfrac {x+3}{7}}$

${:}\longrightarrow$$\sf {\dfrac {-2x+8}{35}}={\dfrac {x+3}{7}}$

• Use cross multiplication method

${:}\longrightarrow$$\sf 35 (x+3)=7 (-2x+8)$

${:}\longrightarrow$$\sf 35x+105=-14x+56$

${:}\longrightarrow$$\sf 35x+14x=56-105$

${:}\longrightarrow$$\sf 49x=-49$

${:}\longrightarrow$$\sf x={\dfrac {-49}{49}}$

${:}\longrightarrow$${\underline{\boxed{\bf{x=(-1)}}}}$

Answer 2

Answer:

$\frac{x - 4}{7} - \frac{x + 4}{5} = \frac{x + 3}{7} \\ \\ = lcm = 35 \\ \\ = \frac{5x - 20 - 7x + 28}{35} = \frac{x + 3}{7} \\ \\ = \frac{ - 2x + 8}{35} = \frac{x +3 }{7} \\ \\ = cross \: mutipliction \\ \\ = 7( - 2x + 8) = 35(x + 3) \\ = ( - 14x) + 56= 35x + 105 \\ = ( - 14x) - 35x = 105 - 56 \\ = ( - 49x) = 49 \\ \\ = x = \frac{ - 49}{49} \\ \\ = x = (-1)$