Prime factor is a factor that is a prime number.
Prime factors of :
8 : 2 × 2 × 2. Also can be written as

12 : 2 × 2 × 3. Also can be written as

20 : 2 × 2 × 5. Also can be written as

30 : 2 × 3 × 5
56 : 2 × 2 × 2 ×7. Also can be written as

70 : 2 × 5 × 7
You can find all of them by using Factor Tree [ as shown in the picture] or Dividing by prime numbers.
(i) Note that it is given to you that 3a + 2b = 9
You are trying to find the value of 9a + 6b. Find what is multiplied to both the variable a & b. Divide:
(9a + 6b)/(3a + 2b) = 3
Next, multiply 3 to the 9 on the other side of the equation:
3 x 9 = 27
27 is the value of 9a + 6b.
(ii) Note that it is given to you that 8x + 6y = 60
You are trying to find the value of 4x + 3y. Find what is multiplied to both the variable x & y. Divide:
(8x + 6y)/(4x + 3y) = 2
Next, divide 2 from the 60 on the other side of the equation:
60/2 = 30
30 is the value of 4x + 3y.
~
Answer:
39
Step-by-step explanation:
1. Subtract the numbers ... 3(3×3+4)
2. Multiply the numbers ... 3(9+4)
3. Add the numbers ... 3×13
4. Multiply the numbers ... 39
• Climate change increases local plant species richness, at least temporarily
• Empirical and modeled data suggest an increase of ∼5% per decade in cool regions
• Climatic perturbation is identified as a process driving biodiversity accrual
• Uneven global coverage of field data could be obscuring other climatic effects