Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
Answer:
So since you have the ratio of 1 : 4
we need to find 3 : x
since 1*3 = 3. We multiply all by 3
4*3 =12.
Answer is 12
Answer:
hello : 256 words
Step-by-step explanation:
2 minutes and 30 = (2×60)+30=150seconds
4 minutes = 4 ×60 = 240 seconds
150seconds →160 words
240 seconds → x ?
x = (160×240) / 150 = 38400/150= 256 words
<span>5<span>2–√ i would believe</span></span>
31,
because when you divide 42 and 12 to get the other two sides you get 3.5 and
3.5+3.5+12+12=31
