Answer:
see explanation
Step-by-step explanation:
Given
4
- 5a² + 1 = 0
Use the substitution u = a², then equation is
4u² - 5u + 1 = 0
Consider the product of the coefficient of the u² term and the constant term
product = 4 × 1 = 4 and sum = - 5
The factors are - 4 and - 1
Use these factors to split the u- term
4u² - 4u - u + 1 = 0 ( factor the first/second and third/fourth terms )
4u(u - 1) - 1(u - 1) = 0 ← factor out (u - 1) from each term
(u - 1)(4u - 1) = 0
Equate each factor to zero and solve for u
u - 1 = 0 ⇒ u = 1
4u - 1 = 0 ⇒ 4u = 1 ⇒ u = 
Convert u back into terms of a, that is
a² = 1 ⇒ a = ± 1
a² = ⇒ a = ± 
Solutions are a = ± 1 , a = ±
C. 0.25 because you divide 0.06 by 0.24
Answer:
67
Step-by-step explanation:
● -(x + 3) + (y - 5) + (z - 6)
● -x - 3 + y - 5 + z - 6
● (-x + y + z) + (3 -5 -6)
● 75 + 3 - 11
● 78 - 11
● 67
Answer:
Ann would need 3 h to complete the remainder of the Job.
Step-by-step explanation:
Step 1.
The "speed" that each girl has to do the work is determined as:
- Tina:
, it means that Tina complete one twelveth of the job each hour. - Ann:
, it means the Ann completes one eighth of the job each hour.
Step 2.
The amount of work done by Tina in 9 hours, is obtain multiplying by the "speed" calculated in step 1:
Amount of work done= 
. It means that <em>Tina completes two thirds of the work in 9 h.</em>
Step 3.
The remaining job is calculated as 
. It means that <em>still remains is one third of the job to be completed</em>.
Step 4.
The time required for Ann to complete the job is calculated dividing the remaining of the job by the "speed" of Ann to do the job.
. It means that <em>Ann would complete the job in another 3 hours</em>.
