so you have to get rid of one variable first to get the value of one. so i multiplied 3a-4b=10 by 4 to get 12a-16=40 and 3b+4a=6 by -3 to get -12a-9b=-18 and added them together to get -25b=22. then you get b by itself and you get b= -0.88. then you go back to the original equations and put the value of b in instead of the variable to get a=2.16 so if a=x and b=y the point of intersection would be (2.16,-0.88) but if b=x and a=y it would be (-0.88,2.16)
hope this helped
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