Answer:
Step-by-step explanation:
Ok here it is:
4x-5y=40
2x+10y=20
I used the second equation and decided to get x
2x+10y=20
Subtract 10y from both sides.
2x=-10y+20
Divide both sides by 2
x=-5y+10
Put that in for x for first equation
4(-5y+10)-5y=40
Distribute the 4
-20y+40 -5y =40
Combine like terms
-25y+40=40
Subtract 40 from both sides
-25y=0
Divide by -25 on both sides
y=0
Substitute the y in for the 2nd equation
2x+10(0)=20
2x=20
Divide both sides by 2
x=10
So x=10 and y=0
What?
i dont know maybe...hmmmm
Answer:
65
Step-by-step explanation:
the sum of interior angles in a triangle equal to 180°
so 45+70=115
180-115=65
Answer:
a couple of irrational numbers: -16±4√19, approximately {1.436, -33.436}
Step-by-step explanation:
Your question can be cast as the quadratic equation
x² +32x -48 = 0
The solutions can be found using the quadratic formula:
x = (-32 ±√(32² -4(1)(-48)))/(2(1)) = -16±√304 = -16±4√19
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<em>Comment on the equation we used</em>
We notice that when p and q are roots, the equation can be written ...
(x -p)(x -q) = 0 = x² -(p+q)x +pq
You want p+q = -32, pq = -48, so the equation is ...
x² -(-32)x +(-48) = 0
x² +32x -48 = 0 . . . . . . with parentheses eliminated
