How do you solve #(x-3)(x+7)=0#?

2 Answers
Apr 20, 2016

Answer:

#x=3color(white)("XX")orcolor(white)("XX")x=-7#

Explanation:

If #(a xx b) = 0# then either #(a=0)# or #(b=0)#

Based on this observation, we see that if #(x-3)(x+7)=0# then
either
#color(white)("XXX")x-3=0color(white)("XX")rarrcolor(white)("XX")x=3#
or
#color(white)("XXX")x+7=0color(white)("XX")rarrcolor(white)("XX")x=-7#

Apr 20, 2016

Answer:

#x={-7,3}#

Explanation:

#(x-3)(x+7)=0#

#if (x-3)=0" " rArr" "x=3#

#if(x+7)=0" "rArr" "x=-7#

#x={-7,3}#