Question

(4-y)²-y(y+1) при y= - 19

Answer 1

Раскроем скобки

-y^2 с y^2 взаимно уничтожаются

16-8y+y^2-y^2-y=16-9y=16-9×(-19)=16+9×19=16+171=187

Answer 2

To evaluate the expression (4-y)²-y(y+1) when y = -19, we substitute -19 for y in the expression and perform the calculations:

(4 - (-19))² - (-19)(-19 + 1)

Simplifying:

(4 + 19)² - (-19)(-18)

(23)² - (-19)(-18)

529 - (-19)(-18)

Now, let's calculate (-19)(-18):

(-19)(-18) = 342

Substituting this value back into the expression:

529 - 342

Finally, we evaluate the subtraction:

529 - 342 = 187

Therefore, when y = -19, the expression (4-y)²-y(y+1) evaluates to 187.