X+ y = 8
1/2x - 1/2y = 3

do these equations have one solution, no solution, or infinitely many solutions?

No solution

Step-by-step explanation:

-x + y = 8(1)

1/2x - 1/2y = 3(2)

Multiply (2) by 2

x - y = 6 (3)

Adding (1) and (3)

-x + x + y - y = 8 + 3

x and y are both eliminated so no solution

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.

the answer is; biodiversity resulting from few ancestors

adaptive radiation occurs when a population is subjected to a large natural environment with spatial ecological variations. the parts of the population in the different ecologies begin to adapt to their local environments. due to non-random mating across the large populations, this causes the different populations from the large population to speciate within their local environments. they, therefore, diverge to different species sharing a common ancestor.