Let there be 2x science and 5x art books
<span>science books sold = 2x × 0.2 = 0.4x </span>
<span>science books unsold = 2x – 0.4x = 1.6x </span>
<span>art books sold = 5x × 0.2 = x </span>
<span>art books unsold = 5x – x = 4x </span>
<span>total books unsold = 1.6x + 4x = 5.6x </span>
<span>5.6x = 2240 </span>
<span>x = 400 </span>
<span>2x science = 800 </span>
<span>and 5x art books = 2000 </span>
1. The growth rate equation has a general form of:
y = A (r)^t
The function is growth when r≥1, and it is a decay when
r<1. Therefore:
y=200(0.5)^2t -->
Decay
y=1/2(2.5)^t/6 -->
Growth
y=(0.65)^t/4 -->
Decay
2. We rewrite the given equation (1/3)^d−5 = 81
Take the log of both sides:
(d – 5) log(1/3) = log 81
d – 5 = log 81 / log(1/3)
d – 5 = - 4
Multiply both sides by negative 1:
- d + 5 = 4
So the answer is D
- Answer & step-by-step explanation:
<em>a) impossible</em>
<em>b) the sum of the angles in a triangle is 180°</em>
<em>63° + 59° + 57° = 179°</em>
