Question

Solve the simultaneous equations j-k= 2 and j2 + 2k=8. Give the answer in three decimal places.

Answer is j=2.606, j=4.606 and k=0.606, k=-6.606

Can you show me how to do it step by step
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Answer 1

j=2.606, j=-4.606 and k=0.606, k=-6.606

Explanation:

First step is to merge the formulas so that you are left with one combined equation with only one variable. Let's go for j, so we won't have to fiddle with the quadratic term:

First we convert j-k=2 to k=j-2, then we plug in this value for k in the other equation:

j² + 2(j-2) = 8

j² +2j -4 = 8

j² + 2j -12 = 0

This we can solve using the quadratic formula:

j = (-2 ± √(2²-4·1·-12) ) / 2

= (-2 ± √52)/2

= -1 ± √13

So j ≈ 2.6056 or j≈-4.6056

k can be found by subtracting 2.

Answer 2

Explanation:

hello :

here is an solution :