Question

Which of the following equations has a positive solution for $x$?

• A. $3x+10=1$
• B. $2+5x=17$
• C. $13-2x=21$
• D. $1-5x=11$

Answer 1

The correct option is B $2+5x=17$

Solving the equation in option a:
$3x+10=1$
Subtracting 10 on both sides,
$3x=1-10=-9$
Dividing by 3 on both sides,
$x=\frac{-9}{3}=-3$

Solving the equation in option b:
$2+5x=17$
Subtracting 2 on both sides,
$5x=17-2=15$
Dividing by 5 on both sides,
$x=\frac{15}{5}=3$

Solving the equation in option c:
$13-2x=21$
Subtracting 13 on both sides,
$-2x=21-13=8$
Dividing by -2 on both sides,
$x=\frac{8}{-2}=-4$

Solving the equation in option d:
$1-5x=11$
Subtracting 1 on both sides,
$-5x=11-1=10$
Dividing by -5 on both sides,
$x=\frac{10}{-5}=-2$