OG详解-OG8 数学1 Q17

Choice A is correct. To express 4j +9 in terms of p and k, the given equation must be solved for 4j +9. Since it’s given that j is a positive number, 4j +9 is not equal to zero. Therefore, multiplying both sides of the given equation by 4j +9 yields the equivalent equation p(4j+9)= k. Since it’s given that p is a positive number, p is not equal to zero. Therefore, dividing each side of the equation p(4j+9)=k by p yields the equivalent equation 4j+9=kp​​ .
Choice B is incorrect. This equation is equivalent to p = 4j+9k​​ . Choice C is incorrect. This equation is equivalent to p = k-4j-9. Choice D is incorrect. This equation is equivalent to p = k(4j+9).