180 I think not sure if I am right
Answer:
value of a.b = -4
Step-by-step explanation:
We need to find a.b
a= 4i-4j
b = 4i+5j
We know that i.i =1, j.j=1, i.j =0 and j.i=0
a.b = (4i-4j).(4i+5j)
a.b = 4i(4i+5j)-4j(4i+5j)
a.b = 16i.i +20i.j-16j.i-20j.j
a.b = 16(1) +20(0)-16(0)-20(1)
a.b = 16 +0-0-20
a.b = 16-20
a.b =-4
So, value of a.b = -4
Your answer would be y + 9 = m(x + 6)
Answer:
Read step by step explanation
Step-by-step explanation:
The owner already knows that the limit for the average time delivered pizzas is 38 minutes. So we conclude
1.-The resulting mean from sample data ( x ) ( 27 customers) need to be smaller than 38 minutes, any value of sample above 38 minutes means more time for the delivery action and will indicate a failure for the future project
2.-As sample size is smaller than 30 the test has to be t-student one tail test to the left
Test hypothesis
Null hypothesis H₀ x = 38
Alternative hypothesis Hₐ x < 38
We should test at a significance level α = 0,05 (α = 5%)
If the result of the test is to accept H₀ delivery project won´t be implemented, if on the other hand, H₀ is rejected then in the condition of the alternative hypothesis we accept Hₐ the sample indicates that we have a smaller average time than 38 minutes.