Question

(14а + 27b) -2(7a-13,5b)+6, если а= -2,4 b= - 8\27​

Answer 1

Раскроем скобки и приведём подобные слагаемые:

= 14а + 27b - 14a + 27b + 6 = (14a - 14a) + (27b + 27b) + 6 =

= 0a + 54b + 6

если а = - 2,4       b = - 8/27

0 · (-2,4) + 54 · (-8/27) + 6 = 0 + 2 · (-8) + 6 = - 16 + 6 = - 10.

Ответ: (-10).

Answer 2

To evaluate the expression (14a + 27b) - 2(7a - 13.5b) + 6 with the given values a = -2.4 and b = -8/27, we substitute these values into the expression and simplify it step by step:

(14a + 27b) - 2(7a - 13.5b) + 6

Substitute the values of a and b:

(14(-2.4) + 27(-8/27)) - 2(7(-2.4) - 13.5(-8/27)) + 6

Simplify the expression inside each set of parentheses:

(-33.6 - 64/27) - 2(-16.8 + 108/27) + 6

Convert the fractions to a common denominator:

(-33.6 - 64/27) - 2(-16.8 + 4) + 6

Simplify the expressions:

(-33.6 - 64/27) - 2(-12.8) + 6

Now, let's simplify further:

To subtract fractions, we need a common denominator:

-33.6 - 64/27 = -33.6 - (64/27)(27/27) = -33.6 - 1728/27 = -33.6 - 64 = -97.6

-2(-12.8) = 25.6

Substitute the simplified values back into the expression:

-97.6 - 25.6 + 6

Combine like terms:

-123.2 + 6 = -117.2

Therefore, the value of the expression (14a + 27b) - 2(7a - 13.5b) + 6, when a = -2.4 and b = -8/27, is -117.2.