X+ y = 44
x - y = 6
—————
2x = 50
x = 25
y = 44-x = 19
1.50c + 2.50a = 1100
c + a = 500
multiply the second equation by -1.50
1.50c + 2.50a = 1100
-1.50c - 1.50a = -7.50
Sec t (theta) - 2 = 0
sec t = 2
1/ cos t = 2
cos t = 1/2
Answer:
t = π / 3 + 2 k π , or : t = 5 π / 3 + 2 kπ,
k ∈ Z
Y=kx
12=-4k
k = -3
so when y = 15
y = kx
15 = -3x
x = -5
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$50 / 0.04 = $1250 (4% interest)
so
1250 * 0.06 = $75
answer
interest $75 at 6%
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y = kx
1/4 = 4k
k = 1/16
when x = 5
y = kx
y = 1/16(5)
y = 5/16
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y = kx
-5 = 4k
k = -5/4
direct equation
y = -5/4x