Answer:
4
Step-by-step explanation:
That is the multipliative identity property.
Answer:
A, B, C and D. are solutions.
Step-by-step explanation:
x^2 + y^2 = 13
x^2 - y^2 = 5
Check which roots fit the original equations:
If x = 3, A gives
9 + y^2 = 13 giving y = +/- √4 = 2 or -2.
Now plug in x = 3 and y = 2 in the second equation:
9 - (2)^2 = 5
Therefore (3,2) is a solution of the 2 equations.
Following the same procedure for B, C and D:
B. Substituting x = 3 and x = -2 fits both equations so (3, -2) is a solution.
The same is true for C and D.
