FACTORISATION IS BASICALLY FINDING LIKE-TERMS.
1. FIND THE HCF OF 8. HERE, THE HCF IS 8. ALSO, CHECK ALL THE LIKE-TERMS. LIKE-TERMS ARE OUTSIDE THE BRACKET AND UNLIKE TERMS ARE INSIDE.
2. ADD THE TERMS IN THE BRACKET AND THE TERMS OUTSIDE THE BRACKET FROM STEP 1.
8x + 8y + rx + ry
1. 8 (x + y) + r (x + y)
2. (x +y) (8+r)
<u>Answer:</u>
<u>Step-by-step explanation:</u>
<u>Let's find 'a' using Pythagoras theorem.</u>
- => 4² = 2² + a²
- => 16 = 4 + a²
- => 12 = a²
- => a = √12
- => a = √2 x 2 x 3
- => a = 2√3
- => a = 2 x √3
- => a = 2 x 1.732
- => a = 3.464 = 3.5 (Estimated)
Hoped this helped.

Answer:
A
Step-by-step explanation:
The student must have thought that every single arrowhead is a line of symmetry, so since there are 10 arrowheads, there must be 10 lines of symmetry. This is incorrect because if you look closely at the diagram, each line has 2 arrowheads, so the student is overcounting by a factor of 2. They should have just counted the number of lines, not arrowheads. Therefore, there must be 10/2 = 5 lines of symmetry, not 10. Hope this helps!