Solve the Triangle Equation: △ - 7 = 80

The problem involves solving a simple algebraic equation:

$\triangle - 7 = 80$

• Step 1: To solve for $\triangle$, we need to isolate it on one side of the equation. We can do this by adding 7 to both sides of the equation to reverse the subtraction.

$\triangle - 7 + 7 = 80 + 7$

This simplifies to:

$\triangle = 87$

The value of the triangle symbol $\triangle$ is $87$.

Therefore, the solution to the problem is $\triangle = 87$, which corresponds to choice 4 in the provided list of answer choices.