Answer:
x = 1 ±2sqrt(5)
Step-by-step explanation:
2x^2-4x-9=29
Add 9 to each each side
2x^2-4x-9+9=29+9
2x^2-4x=38
Divide by 2
2/2x^2-4/2x=38/8
x^2 -2x =19
Complete the square
x^2 -2x + (-2/2)^2 = 19 +(-2/2)^2
x^2 -2x +1 = 19+1
(x-1)^1=2 = 20
Take the square root of each side
sqrt((x-1)^2) = ±sqrt(20)
x-1 = ±sqrt(20)
Add 1 to each side
x-1+1 = 1 ±sqrt(20)
x = 1 ±sqrt(20)
Simplifying the square root of 20
x = 1 ±sqrt(4)sqrt(5)
x = 1 ±2sqrt(5)
Answer:
47.25
Step-by-step explanation:
8.89 is about 9.
So, we have 9(5.25)=9(5)+9(0.25)=45+2.25=47.25
(x + 1)·(x + 1 + 11) = (x + 4)·(x + 4 + 1) --> x = 2
Tools like "photomath" are able to help you solving such equations.
Answer:
22
Step-by-step explanation:
(5x-7 )+(4x-11)=180 ( it equals 180 because those two angles equal 180)
Then add the similar things together
5x+4x=9x
-7-11= -18
9x-18=180, add 18 on both sides to get 9x alone
9x=180, then divide 180 by 9 to get x alone
x=22
Answer: 9
Step-by-step explanation:
Based on the information given in the question, the expected number of people who pass will be calculated as:
= Probability of passing the driving test × Number of people tested
= 65% × 15
= 0.65 × 15
= 9.75
Therefore, expected number of people who pass is 9.