Answer:
2 • (x - 20) • (x + 5) • (x + 40)
Step-by-step explanation:
3p + 2n = 8.25 ....multiply by 2
2p + 3n = 8 .........multiply by -3
-------------------
6p + 4n = 16.5 (result of multiplying by 2)
-6p - 9n = - 24 (result of multiplying by -3)
-------------------add
-5n = - 7.5
n = -7.5 / -5
n = 1.50 .............notebooks cost 1.50 each
2p + 3n = 8
2p + 3(1.50) = 8
2p + 4.50 = 8
2p = 8 - 4.50
2p = 3.50
p = 3.50/2
p = 1.75......pens cost 1.75 each
so 2 pens and 2 notebooks cost : 2(1.75) + 2(1.50) = $ 6.50 <==
Answer:
300
Step-by-step explanation:

Since 225 is 75% of a whole, write the proportion such that 225 corresponds to 75% and x, the number we're searching for, corresponds with 100%
Cross multiply to solve and divide by 75 to isolate x:
225 x 100 = 75x
22500 = 75x
300 = x
2(x+7) + x=20
(2)(x) + (2)(7) + x=20 Distribute
2x+14 + x =20
(2x+x) + (14) =20 Combine Like Terms
3x+14=20
- 14 -14 Subtract 14 from both sides
3x = 6
3x/3 6/3 Divide Both Sides by 3
x = 2
Let me know if you still don't understand