<span>Any ordered pair in a system that makes all the equations true
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I hope this helps you
take both of sides paranthesis square
(2a+7b)^2=(11)^2
4a^2+2.4a.7b+49b^2=121
4a^2+49b^2+56.2=121
4a^2+49b^2=9
Depends on the calculator you have at your disposal. If it's one of the TI-83 series, you can use the built-in 'fnint' function.
https://brownmath.com/ti83/integr.htm
Hopes this can help
<span>Two equations that have the same solution are called equivalent equations e.g. 5 +3 = 2 + 6. And this as we learned in a previous section is shown by the equality sign =. An inverse operation are two operations that undo each other e.g. addition and subtraction or multiplication and division. You can perform the same inverse operation on each side of an equivalent equation without changing the equality.</span>