Question

1+6+11+16+-------+x=148​

Answer 1

36 is the value of x

comen dff = 5

Answer 2

Answer:

x=36

Step-by-step explanation:

Here, a= 1, d= 5

and, x = a+(n-1)d  .......................... (i)

►$\frac{x-a}{d}+1$ = n   .................. (ii)

summation of A.P. = 0.5n(2a+(n-1)d) = 148

► 0.5( $\frac{x-a}{d}+1$  ) (a+a(n-1)d)= 148     (from.. ii)

► 0.5 ( $\frac{x-1}{5}+1$ ) (a+x) = 148     (from .. i )

► 0.5 ( $\frac{x+4}{5}$ ) (1+x) = 148

► (x+4)(x+1) = 1480

► x² + 5x + 4 - 1480 = 0

► x² + 5x - 1476

► x² +41x -36x -1476=0

►(x+41)(x-36) = 0

so, x = 36