Question

13. Find the value of a + b + c - ab-bc-
ca, if a = 2b = -2 and c = 1.
(A) 7
(B) 12
(C) 13
(D) 1
(E) None of these
14. If x + - = 13, then the value of x
is:
х
х
(A) 7171
(B) 167
(C) 1165
(D) 1161
(E) None of these​

Answer 1

Answer:

13.) E) None of the above. Ans = 5

14.)  Que incomplete

Step-by-step explanation for 13):

$a=2, b=-2, c=1$

$=> a + b + c - ab-bc- ca = 2 + (-2) + (1) - (2)(-2) - (-2)(1) - (1)(2)\\ => a + b + c - ab-bc- ca = 2 - 2 + 1 + 4 + 2 - 2\\=> a + b + c - ab-bc- ca = 5$

(Hope it Helps)