Question

evaluate \\(5r^2 + r\\) for \\(r = 9\\).

when \\(r = 9\\), \\(5r^2 + r = \square\\).

Explanation:

Substitute the variable value

$$ \text{Substitute } r = 9 \text{ into } 5r^2 + r: $$

$$ 5(9)^2 + 9 $$

Evaluate the exponent

$$ 9^2 = 81 $$

$$ 5(81) + 9 $$

Multiply and add

$$ 5 \times 81 = 405 $$

$$ 405 + 9 = 414 $$

Answer:

When \(r = 9\), \(5r^2 + r =\) <blank>414</blank>.