First we will find the 11th term
an = a1 + (n-1) * d
a11 = 12 + (11 - 1) * 5
a11 = 12 + 10 * 5
a11 = 12 + 50
a11 = 62
now we use the sum formula...
Sn = (n (a1 + an)) / 2
S11 = (11 (12 + 62)) / 2
S11 = (11 (74)) / 2
S11 = 814/2
S11 = 407
Answer:
x = -56
Step-by-step explanation:
x/7 = -8
Multiply each side by 7
x/7 *7 = -8*7
x = -56
Answer:
10.75
Step-by-step explanation:
43 divided by 4
Answer:x=1
Step-by-step explanation:
Step-by-step explanation:

Distribute into 5x² into (3x +2).

The simplified expression is <em>15x³ + 10x²</em>