What are angles FHG and GHI?

 

FHI is the total of FHG and GHI.  And it's given that FHI is 142^o.  

 

So, set it up:  (3x + 6) + (9x – 8) = 142^o   and then just solve for x and plug that value into each expression. 

 

Read no farther if you can take it from here. 

 

Otherwise:                                          (3x + 6) + (9x – 8)  =  142^o  

 

Add up the like terms                          3x + 9x + 6 – 8  =  142  

                                                                       12x – 2  =  142 

                                                                       12x        =  144  

 

                                                                                  x  =  12  

 

Plug in the value into each angle               (3 • 12) + 6  =    42^o  angle FHG  

                                                                   (9 • 12) – 8  =  100^o  angle GHI  

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