Question

Evaluate the expression `5x^{2}+2y` when `x\ =\ -3` and `y\ =0.25`.

write in decimal form

Answer 1

To evaluate the expression \(5x^{2}+2y\) when \(x = -3\) and \(y = 0.25\), we follow these steps:

1. Substitute the values of \(x\) and \(y\) into the expression.
2. Calculate \(x^2\) first:
\[
x^2 = (-3)^2 = 9
\]

3. Substitute the value of \(x^2\) into the expression:
\[
5x^{2} = 5 \cdot 9 = 45
\]

4. Calculate \(2y\):
\[
2y = 2 \cdot 0.25 = 0.5
\]

5. Now, combine the results:
\[
5x^{2} + 2y = 45 + 0.5 = 45.5
\]

So, the final result in decimal form is \(45.5\).