How do you solve #\frac { 16} { x + 4} = \frac { 4} { 7}#?
1 Answer
Sep 30, 2017
Explanation:
#"one way is to use the method of "color(blue)"cross-multiplying"#
#•color(white)(x)a/b=c/drArrad=bc#
#rArr16/(x+4)=4/7larrcolor(blue)"cross-multiply"#
#rArr4(x+4)=16xx7#
#rArr4x+16=112#
#"subtract 16 from both sides"#
#4xcancel(+16)cancel(-16)=112-16#
#rArr4x=96#
#"divide both sides by "4#
#(cancel(4) x)/cancel(4)=96/4#
#rArrx=24#
#color(blue)"As a check"# Substitute this value into the equation and if both sides are equal then it is the solution.
#16/(24+4)=16/28=cancel(16)^4/cancel(28)^7=4/7#
#rArrx=24" is the solution"#
