Is -3 a solution to the equation #-4x+5=-7#?

2 Answers
Mar 2, 2018

No, but #x=3# is a solution.

Explanation:

Substitue -3 into the equation, what do you get?

#-4 *-3 +5# =#12 + 5# = #17#

Do obviously -3 is not a solution.

Find what is the solution:

Rewrite the equation by transposing the terms:

#-4x#= #-7 -5# = #-12#

Get rid of the minus signs

So #x =3 #

Mar 2, 2018

#"No"#

Explanation:

#"if x = - 3 is a solution then it will satisfy the equation"#

#"substitute "x=-3" into the equation"#

#(-4xx-3)+5=12+5=17!=-7#

#rArrx=-3 " is not a solution"#

#-4x+5=-7#

#"subtract 5 from both sides"#

#-4xcancel(+5)cancel(-5)=-7-5#

#rArr-4x=-12#

#"divide both sides by "-4#

#(cancel(-4) x)/cancel(-4)=(-12)/(-4)#

#rArrx=3#

#color(blue)"Check "(-4xx3)+5=-12+5=-7" True"#

#rArrx=3" is the solution"#