Question

- 18 (a + 1/6) - 15 а, если а = 5/12

Answer 1

Вместо а подставим 5/12

-18(5/12 + 1/6)-15(5/12)= -67/4

Answer 2

To find the value of the expression -18(a + 1/6) - 15a when a = 5/12, simply substitute the value of 'a' into the expression and perform the calculations.

Given: a = 5/12

Now, plug in the value of 'a' into the expression:

-18(a + 1/6) - 15a = -18(5/12 + 1/6) - 15(5/12)

Next, simplify each term:

-18(5/12 + 1/6) can be simplified by finding a common denominator for 12 and 6, which is 12. So:

-18(5/12 + 1/6) = -18(5/12 + 2/12) = -18(7/12)

Now, distribute the -18:

-18(7/12) = -7/2

Now, move on to the second term, -15(5/12):

-15(5/12) = -75/12

Finally, add the two terms together:

-7/2 - 75/12

To add these fractions, find a common denominator for 2 and 12, which is 12:

-7/2 = -42/12

Now, the expression becomes:

-42/12 - 75/12

Combine the numerators and keep the common denominator:

(-42 - 75)/12 = -117/12

The final answer is:

-117/12, which can be further simplified to -39/4 or -9.75.