Question

2x+5x=2.5^2-1

Answer 1

`=> 7x = 50 - 1`

`=> 7x = 49`

`=> x = 7`

Answer 2

\(2x+5x=2.5^2-1\)

\((2+5).x= 2.25-1\)

\(7.x= 50-1\)

\(7.x=49\)

\(x=49:7=7\)

Answer 3

\(2x+5x=2\cdot5^2-1\)

\(7x=2\cdot25-1\)

\(7x=50-1\)

\(7x=49\)

\(x=7\)

Vậy x = 7

Answer 4

$\Rightarrow 7x=50-1$

$\Rightarrow 7x=49$

$\Rightarrow x=7$