How do you solve #\sqrt { 2x + 10} = 21#?

2 Answers
Dec 3, 2016

Square both sides then solve for x. Answer: #x = 431/2#

Explanation:

Square both sides:

#2x + 10 = 441#

#2x = 431#

#x = 431/2#

Dec 3, 2016

#x=431/2\leftrightarrow215.5#

Explanation:

Given #\sqrt(2x+10)=21# we will solve for #x#


calculations
square both sides #(\sqrt(2x+10))^2=(21)^2#
simplify #2x+10=441#
subtract 10 from both sides #2x\cancel(+10)\cancel(\color{seagreen}{-10})=441\color(seagreen)(-10)#
simplify #2x=431# ...
now divide both sides by 2 #(\cancel(2)x)/\cancel(\color(indianred)(2))=431/\color(indianred)(2)#
simplify #x=431/2=215.5#

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