Answer:
see explanation
Step-by-step explanation:
Given
x² - 3x - 40 = 0
Consider the factors of the constant term (- 40) which sum to give the coefficient of the x- term (- 3)
The factors are - 8 and + 5, since
- 8 × 5 = - 40 and - 8 + 5 = - 3, thus
(x - 8)(x + 5) = 0 ← in factored form
Equate each factor to zero and solve for x
x - 8 = 0 ⇒ x = 8
x + 5 = 0 ⇒ x = 5
------------------------------------------------------
Given
4x² - 81 = 0 ← this is a difference of squares and factors in general as
a² - b² = (a + b)(a - b), thus
4x² - 81
=(2x)² - 9²
= (2x + 9)(2x - 9) = 0 ← in factored form
Equate each factor to zero and solve for x
2x + 9 = 0 ⇒ 2x = - 9 ⇒ x = - 
2x - 9 = 0 ⇒ 2x = 9 ⇒ x = 
Answer:
Using PEMDAS, we would first divide 24/8=3. Then, since there is no multiplication or division left, we can finish up with adding and subtracting. So, 48+3-22=29.
So 29 is the answer.
The present age of mother and her daughter respectively are; 40 and 10 years respectively.
<h3>How to Solve Algebra Word Problems?</h3>
Let x and y be the present age of mother and her daughter respectively.
Therefore;
x + y = 50
x = 50 − y .....(1)
After 20 years, mother's age will be twice her daughter's age at the time. Thus;
x + 20 = 2(y + 20)
x − 2y = 20 .....(2)
Plugging eq 1 into eq 2 gives us;
50 − y − 2y = 20
3y = 30
y = 10
Thus;
x = 50 − 10
x = 40
Thus, the present age of mother and her daughter is 40 and 10 years respectively.
Translation of the question into English is;
The sum of the present ages of mother and her daughter is 50 years. After 20 years, mother's age will be twice her daughter's age at the time. Find their present ages.
Read more about Algebra Word Problems at; brainly.com/question/21405634
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Answer:
Cross-sectional study.
Step-by-step explanation:
- In a cross-sectional study, data are observed, measured, and collected at one point in time.
- In a prospective (or longitudinal) study, data are collected in the future from
groups sharing common factors.
- In a retrospective (or case-control) study, data are collected from the past by going
back in tirme (through exanmination of records, interviews, arıd so on).
Hope this Helps!!
Answer:
D
Step-by-step explanation:
sine= opposite/hypotenuse
cosine= adjacent/hypotenuse