Using the Pythagorean theorem:
X = sqrt(26^2 - 10^2)
X = sqrt(676-100)
X = sqrt(576)
X = 24
Answer: 24
To find which point is NOT on the line y = 5x + 1, we just need to plug each point into equation y=5x+1 to see which one point satisfies this equation.
check for (1,6)
y=5x+1
or 6=5*1+1
or 6=5+1
or 6=6
Which is TRUE.
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check for (2,11)
y=5x+1
or 11=5*2+1
or 11=10+1
or 11=11
Which is TRUE.
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check for (0,1)
y=5x+1
or 1=5*0+1
or 1=0+1
or 1=1
Which is TRUE.
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check for (-1,6)
y=5x+1
or 6=5*(-1)+1
or 6=-5+1
or 6=-4
Which is FALSE.
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Since only point (-1,6) fails to satisfy the given equation hence point (-1,6) is the final answer.
(2/3)n - 6 = 2
Add 6 to both sides.
(2/3)n = 8
Divide by 2/3.
n = 9 / (2/3)
n = 27/2, or 13.5