<span>(13a + 5b) + (a + 5b - 3)
</span><span>
= 13a + 5b + a + 5b - 3
= 14a + 10b - 3 </span>
Answer:
1. -2
2. 21^2
Step-by-step explanation:
Half.
When you divide something by two, you halve its value.
Answer: 25x² - 64
<u>Step-by-step explanation:</u>
(5x + 8)(5x - 8)
= 5x(5x - 8) + 8(5x - 8)
= 25x² - 40x + 40x - 64
= 25x² + 0x - 64
= 
NOTE: descending powers means the biggest exponent goes first, then the next biggest exponent, etc.
For example: x⁴ then x³ then x² then x then the number (which is actually x⁰)
There is no information here, could you add more. There are no lines for us to help you with so this makes it confusing for others, add more information for us to be able to help.