Answer:
There's no picture so C could be 11, or 5, or 24, the answers are endless
Step-by-step explanation:
D becaucause you have to do 12x8 and then 12x5 and whatever 12x8 is you but the answer bring down the + and do 12x5
X+y = 12
x-y = 3
x = 3+y
Substitute it in 1st equation,
3+y+y=12
2y = 9
y = 4.5
Substitute it in 1st eq.,
x = 12-4.5 = 7.5
So, the two numbers are 7.5 & 4.5
Hope this helps!
Answer:
x = - 1 ± 2i
Step-by-step explanation:
we can use the discriminant b² - 4ac to determine the nature of the roots
• If b² - 4ac > , roots are real and distinct
• If b² - 4ac = 0, roots are real and equal
• If b² - ac < 0, roots are not real
for x² + 2x + 5 = 0
with a = 1, b = 2 and c = 5, then
b² - 4ac = 2² - (4 × 1 × 5 ) = 4 - 20 = - 16
since b² - 4ac < 0 there are 2 complex roots
using the quadratic formula to calculate the roots
x = ( - 2 ±
) / 2
= (- 2 ± 4i ) / 2 = - 1 ± 2i