25x² + 1 = 5
25x² + 1 - 5 = 0
25x² - 4 = 0 By difference of two squares
(5x)² - (2)² = 0
(5x - 2)(5x + 2) = 0
5x - 2 = 0 or 5x + 2 = 0
5x = 0 + 2 5x = 0 - 2
5x = 2 5x = -2
x = 2/5 x = -2/5
x = 0.4 x = -0.4
x = + 0.4 or -0.4
C.) 3:5 = 12:20
It is this because you can divide them evenly into each other. 3*4 is 12 and if you do 5*4 it is 20. Boo yeah
Answer:
7
Step-by-step explanation:
To solve this, we have to work backwards. If you divide something by 9, and it equals 5, to figure out the number, we need to multiply by 9. 5*9= 45. If four was taken away, we have to add it to 45, which is 49. If a number *7 is 49, then we have to divide by 7 to get the answer. 49/7=7
65 bought 3 or more.
950x0.82=779
779-528=251
251-186=65
Final answer: 65
Step-by-step explanation:
the introduction of a fraction tells us that we are dealing with multiplications, and therefore a geometric sequence (where every new term is created by multiplying the previous term by a constant factor, the ratio r).
I think your teacher made a mistake, or you made one when typing the question in here.
there is no factor r that creates
15×r = 9
and
9×r = 5/27
it would mean that
15 × r² = 5/27
r² = 5/27 / 15 = 5/27 × 1/15 = 5/405 = 1/81
r = 1/9
but 15 × 1/9 = 5 × 1/3 = 5/3 is NOT 9
and 9 × 1/9 = 9/9 = 1 is NOT 5/27
so, this can't be right.
on the other hand
15 × r = 9
r = 9/15 = 3/5
and then
9 × 3/5 = 27/5
so, either the sequence should have been
15, 5/3, 5/27
or (and I suspect this to be true)
15, 9, 27/5
under that assumption we have
s1 = 15
r = 3/5
sn = sn-1 × r = s1 × r^(n-1) = 15 × (3/5)^(n-1)
s10 = 15 × (3/5)⁹ = 15 × 19683/1953125 =
= 3 × 19683/390625 = 59049/390625 =
= 0.15116544 ≈ 0.151
