Trigonometric ratios are sine, cosine, and tangent (opposite side over hypotenuse, adjacent side over hypotenuse, and opposite side over adjacent side, respectively); if you wanted to prove that one of the angles of the triangle is 90º, then the cosine of that angle would be 0, the sine would be 1, and the tangent would be undefined.
A=p(1+i/m)^mn
A=11,700×(1+0.039÷4)^(4×18)
A=23,527.94
Y = 12x - 5x - 2
first simplify the equation by subtracting like terms (in this case):
12x - 5x = 7x
y = 7x - 2
Since you are finding the x, you must isolate the x. Do the opposite of PEMDAS.(Note: because there is a equal sign, what you do to one side, you do to the other)
y = 7x - 2
y (+2) = 7x - 2 (+2)
y + 2 = 7x
(y + 2)/7 = 7x/7
x = (y + 2)/7
x = (y + 2)/7 is your answer
hope this helps