1. She didn’t eat much though she was hungry.

-> She didn't eat much despite her hunger.
2. He couldn’t solve the problem though he is good at maths.

-> He couldn't solve the problem in spite of being good at maths.
3. Mr Pike doesn’t wear glasses though he is over sixty.

-> Mr. Pike doesn't wear glasses despite being over sixty.
4. Although he had much experience in machinery, he didn’t succeed in repairing this machine.

-> In spite of his experience in machinery, he didn't succeed in repairing this machine.
5. Although it got dark, they continued to work.

-> Despite the dark, they continued to work.
6. Although it was noise, I kept on studying.

-> In spite of the noise, I kept on studying.
7. Although it rained heavily, I went to school on time.

-> Despite the heavy rain, I went to school on time.
8. The flight was not delayed though it was foggy.

-> In spite of the fog, the flight was not delayed.
9. He ate all the fruits though they were green.

-> Despite the fruits's being green, he ate all of them.
10. We did the test well though it was difficult.

-> We did the test in spite of its difficulty.
11. Although he is strong, I’m not afraid of him.

-> Despite his strength, I'm not afraid of him.
12. Everybody has great regard for him though he is poor.

-> Everybody has great regard for him despite his poverty.
13. The plane took off though the weather was bad.

-> The plane took off despite the bad weather.
14. He didn’t stop his car though the traffic lights turned red.

-> He didn't stop his car despite the red traffic lights.
15. He studied very well though his life was hard at that time.

-> He studied very well despite his hard life at that time.

\(a,=5xy\left(3x-y+4x^2\right)\)

\(b,=\left(x-4\right)^2-16=\left(x-4+4\right)\left(x-4-4\right)\)

\(=x\left(x-8\right)\)

\(c,=\left(x-5\right)^2-9^2=\left(x-14\right)\left(x+4\right)\)

\(d,=\left(x-y\right)^2-\left(x+5\right)^2=\left(2x-y+5\right)\left(-y-5\right)\)