slope = rise over run = y/x
A (-1,3) slope = 3/-1 = -3
B (1,2) slope = 2/1 = 2
C (-3,-1) slope = -1/-3 = 1/3
2 lines need to be negative reciprocals in order to be a right triangle
negative reciprocal of -3 is 1/3
so this is a right triangle
Answer:
<h2> (-1,1)</h2>
Step-by-step explanation:
Given system is

If we graph, the solution would be the interception point between these two lines, because each linear equation represents a line. The lines are attached.
In the graph, you can observe that the solution is the point (-1,1), that is x = -1 and y = 1.
Now, if we want to solve this system by another method, we can just sum both equations and solve for <em>x</em>


Then, we replace this value in one equation to find the other value

Therefore, the solution is (-1,1)
Answer:
4
Step-by-step explanation:
Let events
A=Nathan has allergy
~A=Nathan does not have allergy
T=Nathan tests positive
~T=Nathan does not test positive
We are given
P(A)=0.75 [ probability that Nathan is allergic ]
P(T|A)=0.98 [probability of testing positive given Nathan is allergic to Penicillin]
We want to calculate probability that Nathan is allergic AND tests positive
P(T n A)
From definition of conditional probability,
P(T|A)=P(T n A)/P(A)
substitute known values,
0.98 = P(T n A) / 0.75
solving for P(T n A)
P(T n A) = 0.75*0.98 = 0.735