X + y = 1
x + 3y = 9
Subtract the second equation from the first.
-2y = -8
divide both sides by -2
y = 4
Plug 4 back into either equation and solve for x.
x + y = 1
x + 4 = 1
subtract 4 from each side
x = -3
(-3, 4)
Answer:
-3+2sqrt7
-3-2sqrt7
Step-by-step explanation:
x^2+6x-9=10
x^2+6x-9-10=0
x^2+6x-19=0
ax^2+bx+c=0
a=1 b=6 c=-19
As cannot be solved by completing square we will use quadratic equation
x= (-b+sqrt(b^2-4ac))/2a and x= (-b-sqrt(b^2-4ac))/2a
x= (-6+sqrt(6^2-4*-19))/2 and x= (-6-sqrt(6^2-4*-19))/2
x=(-6+sqrt(36+76))/2 and x=(-6-sqrt(36+76))/2
x=(-6+4sqrt7)/2 and x=(-6-4sqrt7)/2
x=(-3+2sqrt7) and x=(-3-2sqrt7)
x=2.29 and x= -8.29
4/5+3/5 = 7/5 = 1.4
3.5X5 = 17.5
1.4 + 17.5 = 18.9 = 18 9/10
The others don’t make any sense so it has to be “A”.