b)You are given g(x) = ax + b; You are also given that g(0) = 4 and g(1) = - 6; Find the value of a and the value of b

(Question on topic of algebra taken from June 2016 OCR Past Paper)b) This question may look different to the previous one but it's still only algebra, so it;s pretty much the same. Don't let the unknows scare you. The answer is actually given in the question. The reason I say this is because we get given a general equation ( general implying that it works for any value of x) and then we are given a set of "instructions". g(0) = 4 and g(1) = -6 are INSTRUCTIONS. They tell you what the answer is when zero or 1 are plugged into our general exquation g(x). SO all we have to do is replace the x's in the general equation with the respective value. For g(0) -> g(0) = a(0) + b but this also equals 4 so a(0) + b = 4 hence b = 4. For g(1) -> g(1) = a(1) + b but this also equals -6 so a(1) + b = -6 hence a + b = -6 . We know what b is hence a + 4 = -6 -> a = -10

SR

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