What is the answer to this promblem

9514 1404 393

Step-by-step explanation:

Pick the variable you want to eliminate. Determine the coefficients of that variable in the two equations. Negate one of them. Multiply each equation by the coefficient that came from the other equation.

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To eliminate x

The x-coefficients are 4 and 3. If we negate 4, then the resulting y-coefficient will be positive. We choose to multiply the first equation by 3, the second by -4.

Here is the result of adding those:

  3(4x +5y) -4(3x -2y) = 3(7) -4(-12)   ⇒   23y = 69

To eliminate y

The y-coefficients are 5 and -2. If we negate -2, then the resulting x-coefficient will be positive. We choose to multiply the first equation by 2 and the second by 5.

Here is the result of adding those:

  2(4x +5y) +5(3x -2y) = 2(7) +5(-12)   ⇒   23x = -46

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this