The first one I think not sure
“what is the sum of the angles of a triangle” 180 degrees
<span>2x-1/4(12x+4)=3
</span>⇒ 2x -1/4*(12x) -1/4*4= 3 (distributive property)
⇒ 2x -3x -1= 3
⇒ -x= 3+1
⇒ -x= 4
⇒ x= -4
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Final answer: x=-4~
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2.5 is the geometric mean
