7. tina solved the problem 940 x 56 incorrectly. this is what she wrote 940 x 56 = 5,264 940 × 56 = 5,264
what error did tina make?
A. she added the product of 94 and 6 with the product of 940 and 5.
B. she added the product of 940 and 6 with the product of 940 and 5.
C. she added the product of 940 and 60 with the product of 940 and 50
D. she added the product of 940 and 6 with the product of 940 and 50.

The actual answer for the equation is 52,640.

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2

secant-secant formula:

(whole secant) x (external part) =           (whole secant) x (external part)

(8+y-2) *8=                                           (y+4+6) *6

(y+6)*8 = (y+10) *6

distribute

8y+48 = 6y +60

subtract 6y from each side

2y +48 = 60

subtract 48 from each side

2y = 12

divide by 2

y = 6

sv =     (y+4+6)

sv   = 6+4+6

sv = 16