Step-by-step explanation:
5x + y = 11 (I)
3x - y = 9 (II)
Add equation (I) & (II)
5x + y = 11
3x - y = 9 {add and y will be eliminated and we'll get the value of x}
8x = 20
x = 20/8
x = 2.5
Plugin x = 2.5 in equation (I)
5*2.5 + y = 11
12.5 + y = 11
y = 11 - 12.5
y = -1.5
idk
step-by-step explanation:
x² + 3x + 7 = 0 [ax² + bx + c]
a = 1
b = 3
c = 7
quadratic formula:
(+/- is this ±)
plug in the numbers into the variables
your answer is a