The sign combinations used in 12/(7-4) + 5 × 3 = 19 is correct.
What is the trial method?
Trial and error, or trial by error, is a general method of problem solving. In this method, we keep substituting the value of the variable in the given equation until the value of LHS of the equation is equal to the value of the RHS of the equation.
The given expression is;
[tex]\rm \dfrac{12}{7-4}+5\times 3=19[/tex]
To solve this, the trial and error method will be adopted.
The trial and error method involves trying series of sign combinations in the given expression; whichever works is the right answer.
So, after few attempts the following makes the equation true;
12/(7-4) + 5 * 3 = 19
To check if it's true or not; we simply expand the expression on the left hand side. This gives
[tex]\dfrac{12}{7-4} + 5 \times 3 = 19\\\\ \dfrac{12}{3} + 5 \times 3 = 19\\\\4 + 5 \times 3 = 19\\\\4 + 15 = 19\\\\\ 19 = 19[/tex]
Hence, the sign combinations used in 12/(7-4) + 5 × 3 = 19 is correct.
Learn more aabout trial method here;
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