Question

solve 3f+4/2-6f=-2/5​

Answer 1

-3f=-2/5-4/2

-3f=-2/5-2

-3f=-2-10/5

-3f=-12/5

f=4/5

Answer 2

Answer:

$3f+\dfrac{4}{2}-6f=-\dfrac{2}{5}\quad :\quad f=\dfrac{4}{5}\quad \left(\mathrm{Decimal}:\quad f=0.8\right)$

Step-by-step explanation:

$3f+\dfrac{4}{2}-6f=-\dfrac{2}{5}$

$\mathrm{Group\:like\:terms}$

$3f-6f+\dfrac{4}{2}=-\dfrac{2}{5}$

$\mathrm{Add\:similar\:elements:}\:3f-6f=-3f$

$-3f+\dfrac{4}{2}=-\dfrac{2}{5}$

$\mathrm{Divide\:the\:numbers:}\:\dfrac{4}{2}=2$

$-3f+2=-\dfrac{2}{5}$

$\mathrm{Subtract\:}2\mathrm{\:from\:both\:sides}$

$-3f+2-2=-\dfrac{2}{5}-2$

$\mathrm{Simplify}$

$\mathrm{Simplify\:}-3f+2-2$

$\mathrm{Add\:similar\:elements:}\:2-2=0$

$=-3f$

$\mathrm{Simplify\:}-\dfrac{2}{5}-2$

$\mathrm{Convert\:element\:to\:fraction}:\quad \:2=\dfrac{2\cdot \:5}{5}$

$=-\dfrac{2\cdot \:5}{5}-\dfrac{2}{5}$

$\mathrm{Since\:the\:denominators\:are\:equal,\:combine\:the\:fractions}:\quad \dfrac{a}{c}\pm \dfrac{b}{c}=\dfrac{a\pm \:b}{c}$

$=\dfrac{-2\cdot \:5-2}{5}$

$=\dfrac{-12}{5}$

$\mathrm{Apply\:the\:fraction\:rule}:\quad \dfrac{-a}{b}=-\dfrac{a}{b}$

$=-\dfrac{12}{5}$

$-3f=-\dfrac{12}{5}$

$\mathrm{Divide\:both\:sides\:by\:}-3$

$\dfrac{-3f}{-3}=\dfrac{-\dfrac{12}{5}}{-3}$

$\mathrm{Simplify}$

$\mathrm{Simplify\:}\dfrac{-3f}{-3}:\quad f$

$\mathrm{Simplify\:}\dfrac{-\dfrac{12}{5}}{-3}$

$\mathrm{Apply\:the\:fraction\:rule}:\quad \dfrac{-a}{-b}=\dfrac{a}{b}$

$=\dfrac{\dfrac{12}{5}}{3}$

$\mathrm{Apply\:the\:fraction\:rule}:\quad \dfrac{\dfrac{b}{c}}{a}=\dfrac{b}{c\:\cdot \:a}$

$=\dfrac{12}{5\cdot \:3}$

$\mathrm{Multiply\:the\:numbers:}\:5\cdot \:3=15$

$=\dfrac{12}{15}$

$\mathrm{Cancel\:the\:common\:factor:}\:3$

$=\dfrac{4}{5}$

$f=\dfrac{4}{5}$