Choose the correct answer from the given four options:The 21st term of the AP whose first two terms are –3 and 4 is 17

-137

137

127​

137

Step-by-step explanation:

given AP

t1 = -3 and t2 = 4

using,

d=t1-t2

=4-(-3)

=7

And,

tn=a+(n-1)d

t21=(-3)+(21-1)(7)

t21=137

B) -137

Step-by-step explanation:

a=a1=−3,a2=4

∴d=a2−a1=4−(−3)=4+3=7

37/3

step-by-step explanation:

step 1: simplify both sides of the equation.

7x+8(x+

1

4

)=3(6x−9)−8

7x+(8)(x)+(8)(

1

4

)=(3)(6x)+(3)(−9)+−8(distribute)

7x+8x+2=18x+−27+−8

(7x+8x)+(2)=(18x)+(−27+−8)(combine like terms)

15x+2=18x+−35

15x+2=18x−35

tep 2: subtract 18x from both sides.

15x+2−18x=18x−35−18x

−3x+2=−35

step 3: subtract 2 from both sides.

−3x+2−2=−35−2

−3x=−37

step 4: divide both sides by -3.

−3x

−3

=

−37

−3

x=

37

3