How do you find the real solutions of the equation by graphing #6x^2=48x#?

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Answer 1 · 2016-11-26T16:50:32

#x=0" and "x=8#

#color(blue)("Solving from the graph")#

Given:#" "6x^2=48x#

divide both sides by 6

#x^2=8x#

Subtract 8x from both sides

#x^2-8x=0#

Set as #y=x^2-8x# and plot the graph

Read of the values of #x# for which #y# is 0

Giving: #x=0" and "x=8#

Tony B
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#color(blue)("Solving using maths")#

Given that #x^2-8x=0#

#=>x^2=8x#

Divide both sides by #x#

#color(brown)(x=8 larr" First solution")#

Again consider # x^2=8x#

Known that 0 times any number gives 0

Let #x=0# giving

#x^2=8x" "->" "0xx0=8xx0" "->" "0=0 larr" True"#

#color(brown)("So "x=0 larr" Second solution")#