5. Answer: see explanation
<u>Step-by-step explanation:</u>
If the roots are m and 3m, then x = m and x = 3m
⇒ x - m = 0 and x - 3m = 0
⇒ (x - m)(x - 3m) = 0
⇒ x² - 4mx + 3m² = 0
Since x² + px + q = 0 then p = -4m and q = 3m²
3p² = 3(-4m)² 16q = 16(3m²)
= 3(16m²) = 48m²
= 48m²
3p² = 48m² = 16q ⇒ 3p² = 16q
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6. Answer: 8 or 18
<u>Step-by-step explanation:</u>
The Area of the entire rectangle (A = L × w) is 12 × 10 = 120
The Area of the shaded region is 72, so the Area of the non-shaded region is 120 - 72 = 48.
There are two non-shaded triangles.
- Bigger non-shaded Δ: L = 12-x, w = 10 ⇒

- Smaller non-shaded Δ: L = x, w = x ⇒

Combine the Areas of both triangles and set it equal to the Area of the non-shaded region:

Area of ΔBEF:

Let x be the cost of dryer, y be the cost of washer
x + y =821
x-79 = y
combine 2 equation
we got
x + (x-79) = 821
2x + 79 = 821
2x = 742
x=471
The cost of dryer is $471
Answer:
(-1, -13) is the correct answer
Answer:
486.4
Step-by-step explanation:
640 - (24% × 640) =
(1 - 24%) × 640 =
(100% - 24%) × 640 =
76% × 640 =
76 ÷ 100 × 640 =
76 × 640 ÷ 100 =
48,640 ÷ 100 =
486.4