The equation given in the question has one unknown variable in the ofrm of "x" and there is also a single equation. So it can be definitely pointed out that the exact value of the unknown variable "x" can be easily determined. Now let us focus on the equation given in the question.
x/35 = 7
x = 35 * 7
x = 245
So we can find from the above deduction that the value of the unknown variable "x" is 245. The correct option among all the options given in the question is option "B". I hope the procedure is not complicated for you to clearly understand.
2x - 3y = 3.....multiply by 4
5x - 4y = 4....multiply by -3
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8x - 12y = 12 (result of multiplying by 4)
-15x + 12y = -12 (result of multiplying by -3)
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- 7x = 0
x = 0 <===
AC = √(40²-12²) = √(1600-144) = √1456 = 4√91
tanA = 12/4√91 = 3/√91 = 3√91/91
option а.
