12-4/5(x+15)=4 (do distrib. property first
12-4/5x-12=4 (add -12 for both sides
12-4/5x=16 (subtract 12 for both sides
-4/5x=4 (flip -4/5 like this:5/-4 for both sides
5/-4*-4/5x=4*5/-4 ( the left hand side of the equation will be canceled out so it will be x by itself and multiply 5 and 4 togeher to get 20 and divide by -4
final answer: x=-5
X^2/a^2+y^2/b^2=1
or
x^2/900 + y^2/169 = 1 x^2/1467^2 + y^2/736^2= 1 x^2/736^2 + y^2/1467 = 1 x^2/169 + y^2/900 = 1
45 = 3×3×5
54 = 2×3×3×3
Two number : 3,3
So, the GCD of 45,54 is 3×3= 9
