4 years ago

Find the 12th term of the arithmetic sequence given a3=116 and a7=180

Mathematics

1 answer:

SOVA2 [1]4 years ago

5 0

Answer:

Step-by-step explanation:

nth term = a +(n-1)d

a3 = 116 ; a + 2d = 116 ---------(i)

a7 = 180; a + 6d = 180 -------(ii)

multiply (ii) by -1. so a will be eliminated

a + 2d = 116 ---------(i)

(ii)*-1 -a - 6d = -180 -------(ii) { Now add the two equations}

- 4d = -64

d = -64/-4

d = 16

Plug in the value of d in equation (i),

a + 2*16 = 116

a + 32 = 116

a = 116 - 32

a = 84

12th term = 84 + 11* 16 = 84 + 176 = 260

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A small order of fries at Wendy’s has 90 more calories than the small order of fries at McDonald’s. If together they have 550 ca

S_A_V [24]

Answer:

320 calories

Step-by-step explanation:

Small order of fries at Wendy’s = x calories

Small order of fries at McDonald’s = y calories

x = y + 90
x + y = 550

Substitute x in the second equation

y + 90 + y = 550
2y = 550 - 90
2y = 460
y = 230

Then, x is:

x = 230 + 90 = 320 calories

3 0

3 years ago

AB Complementary SinA = 4/5 find Cos b

Dmitry [639]

Answer:

$cos\:b = \frac{4}{5}$

Step-by-step explanation:

It is given that: a and b are complementary.

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