Question 995454


{{{A=(x-30)}}} 
{{{B=(2x-120)}}} 
{{{C=(1/2+15)}}}...I guess you have {{{C=((1/2)x+15)}}}

the sum of all interior angles in triangle is {{{180}}}°

then you have 

{{{A+B+C=180}}}°

{{{(x-30)+(2x-120)+((1/2)x+15)=180}}}°......solve for {{{x}}}

{{{x-30+2x-120+(1/2)x+15=180}}}°

{{{x-30+2x-120+0.5x+15=180}}}°

{{{3.5x-135=180}}}°

{{{3.5x=180+135}}}°

{{{3.5x=315}}}°

{{{x=315/3.5}}}°

{{{x=90}}}°

now find the measure of all three angles:

{{{A=(x-30)}}} =>{{{A=(90-30)}}}=>{{{A=60}}}
{{{B=(2x-120)}}}=> {{{B=(2*90-120)}}}=> {{{B=60}}}
{{{C=(x/2+15)}}}=>{{{C=(90/2+15)}}}=>{{{C=60}}}