Final answer:
To simplify the expression and evaluate y when x is 10, one must first combine like terms and then substitute the value of x. After simplifying, y is equivalent to -2400.
Step-by-step explanation:
The student's question seems to be about simplifying and evaluating a mathematics equation for a given value of x. However, the question as presented contains a typo or formatting issues which makes it unclear. A possible interpretation of the question asks to simplify and evaluate an expression where y is written in the form y = 10x2 + 25x - 30x2 - 65x when x is 10. To solve this, we would combine like terms and then substitute the value of x.
First, we combine like terms:
y = -20x2 - 40x
Next, we substitute x = 10 into the simplified equation:
y = -20(10)2 - 40(10)
y = -20(100) - 400
y = -2000 - 400
y = -2400
This gives us the value of y when x is 10.