X^2 + y^2 = 25
2x + y = -5.....y = -2x - 5
x^2 + (-2x - 5)^2 = 25
x^2 + (-2x - 5)(-2x - 5) = 25
x^2 + (4x^2 + 20x + 25) = 25
5x^2 + 20x + 25 = 25
5x^2 + 20x = 0
5x(x + 4) = 0
5x = 0 2(0) + y = -5
x = 0 y = -5
x + 4 = 0 2(-4) + y = -5
x = -4 -8 + y = -5
y = 3
solutions are : x = 0, y = -5.....and x = -4, y = 3
to solve this system I first multiplied the second equation by 2 to make the x coefficient equal. then I subtracted equation two from equation one. this eleminated the x. solving for y gave me y=0. then I put 0 back in the original equation and that gave me x=-4.
Answer:
25i
Step-by-step explanation:
Your calculator or your knowledge of powers of 5 will tell you that √625 is 25. The minus sign makes the root imaginary.
Answer:
24
Step-by-step explanation:
Take the number of students and multiply by the percentage to see how many got it right
30 *80%
Change to decimal form
30 *.8 =24
24 students got it correct
