Use the equation of a line: y = mx + c
- “M” stands for the slope
- “C” is the coordinate “y” when the line intercepts the y axis.
Any line which is perpendicular to another has the opposite gradient/slope of the original line: instead of 2, we now have 1/2. Easy way to do this is simply give it the reverse sign (+ or -) and flip the numerator and denominator.
Therefore, we replaced m with 1/2.
Usually to find c and therefore complete the equation, we need a coordinate which the line crosses, to which we substitute its values into y and x and solve for c.
Since we aren’t given that though, we can just do factor of elimination, giving C) as your answer because it is the only one with the gradient which we found.
Answer:
19.34cm
Step-by-step explanation:
Rigth Angled triangle
use SOHCAHTOA
Cos°=adj/hyp
Cos 71=6.3/BC
BC=6.3/COS 71
COS 71°= 0.3256
BC=6.3/0.3256
BC= 19.34cm
A keypad at the entrance of a building has 10 buttons labeled 0 through 9. What is the probability of a person correctly guessing a 9-digit entry code if they know that no digits repeat?
Answer:
the probability of a person correctly guessing a 9-digit entry code if they know that no digits repeat is 0.1
Step-by-step explanation:
We know that probability= number of required outcomes /number of all possible outcome.
From the given information;
the number of required outcome is guessing a 9-digit = 1 outcome
the number of all possible outcome = ¹⁰C₉ since there are 10 numbers and 9 number are to be selected.
Since there are only 9-digit that opens the lock;
the probability of a person correctly guessing a 9-digit entry code is



P = 0.1