Question

Упростите 1) 5(3n-4)-3(n-7) 2) -2,5(k+7)+(5-k) 3) 0,2(p-m)-0,7(2p-4m) Найдите значение при p=-2,3 m=4,5

Answer 1

Ответ:

3) 14,46

Объяснение:

1) 12n+1

2) -3.5k-12.5

3) -1.2p+2,6m

Answer 2

1. 5(3n - 4) - 3(n - 7)

First, distribute the multiplication:

= 15n - 20 - 3n + 21

Combine like terms:

= (15n - 3n) + (-20 + 21)

= 12n + 1

2. -2.5(k + 7) + (5 - k)

First, distribute the multiplication:

= -2.5k - 17.5 + 5 - k

Combine like terms:

= (-2.5k - k) + (-17.5 + 5)

= -3.5k - 12.5

3. 0.2(p - m) - 0.7(2p - 4m)

First, distribute the multiplication:

= 0.2p - 0.2m - 1.4p + 2.8m

Combine like terms:

= (0.2p - 1.4p) + (-0.2m + 2.8m)

= -1.2p + 2.6m

To find the values when p = -2.3 and m = 4.5, substitute those values into the expression:

-1.2(-2.3) + 2.6(4.5)

= 2.76 + 11.7

= 14.46