Question

Знайдіть значення виразу : a)(a-5)^2-a(a+8),якщо а=0,5

Answer 1

(a - 5)² - a(a + 8) = a² - 10a + 25 - a² - 8a = 25 - 18a

25 - 18 * 0,5 = 25 - 9 = 16

Answer 2

To find the value of the expression $(a - 5)^2 - a(a + 8)$ when $a = 0.5$, we simply substitute the value of $a$ into the expression and perform the calculations.

Given that $a = 0.5$, we can plug in this value:

$(0.5 - 5)^2 - 0.5(0.5 + 8)$

Now, let's calculate step by step:

$(0.5 - 5)^2 = (-4.5)^2 = 20.25$

$0.5(0.5 + 8) = 0.5 \times 8.5 = 4.25$

Finally, the value of the expression is:

$20.25 - 4.25 = 16$

So, when $a = 0.5$, the value of the expression $(a - 5)^2 - a(a + 8)$ is 16.