Answer:
Step-by-step explanation:
9x⁴ – 2x² – 7 = 0
Let's say that u = x²:
9u² – 2u – 7 = 0
Factor:
(u – 1) (9u + 7) = 0
u = 1, -7/9
Since u = x²:
x² = 1, -7/9
x = ±1, ±i √(7/9)
Umm.. I have to see the problems, we might not have the same textbooks so
Answer:
Step-by-step explanation:
Change the 2/3 to 4/6
Now the ratio becomes 3:4:6
So the number of each is
3x + 4x + 6x = 520
13x = 520
x = 40
Red = 3*40 = 120
Yellow = 4*40 = 160
Blue = 6 * 40 = 240
Total = 520
