2x+8y=4. x=−3y+5. substitution method

  (x, y) = (14, -3)

Step-by-step explanation:

You are given an expression for x, so it is convenient to use that to substitute for x.

  2(-3y +5) +8y = 4

  -6y +10 +8y = 4 . . . . . eliminate parentheses

  2y = -6 . . . . . . . . . . . . subtract 10, collect terms

  y = -3 . . . . . . . . . . . . . divide by 2

  x = (-3)(-3) +5 = 14 . . . use the second equation to find x

The solution is (x, y) = (14, -3).

-10i^2-4i

step-by-step explanation:

evaluate for p=2,q=5i

(2−4)(2+5i)i

(2−4)(2+5i)i

=−10i2−4i