Rafael ordered some books online and spent a total of \( \$ 89 \). Each book cost \( \$ 5 \) and he paid a total of \( \$ 4 \) for shipping. How many books did he buy? (a) Write an equation that could be used to answer the question above. First, choose the appropriate form. Then, fill in the blanks with the numbers 89,5 , and 4 . Let \( b \) represent the number of books. \( \square b-\square=\square=\square \) \( b=\square \)

4. Na natureza há bactérias que se multiplicam tão rapidamente que dobram de volume a cada minuto. Partindo-se de uma bactérias, sendo \( V(t) \) o volume de uma bactéria analisada após \( t \) minutos, e sendo \( V(t)=V_{0} \times 2^{t} \) a relação que fornece o volume da bactéria no instante t , onde \( V_{0} \) é o volume inicial da bactéria. Determine após quanto tempo, uma bactéria de volume inicial igual a \( 2 \mu \mathrm{~g} \) chega a \( 2048 \mu \mathrm{~g} \).

Aufgabe 6: Gegeben sind \( f(x)=(x-2)^{2}-4 \) und \( h(x)=-x^{2}+2 x+8 \) a) Bestimme und berechne die Scheitelpunkte b) Berechne die Schnittpunkte von \( f(x) \) mit \( h(x) \) c) Berechne die Gerade g die durch die beiden Scheitelpunkte verläuft d) Berechne die Gerade \( k \) die Schnittpunkte von den beiden Parabeln verläuft e) Wo treffen sich die beiden Geraden?

will be cqual, if either \( b=0 \), or \( a^{3}+b^{2}+c^{3}-3 a b c-0 \). If \( a, b, c \) arc rational and \( a+b+c=0 \), show that the roots of \( (b+c-a) x^{2}+(c+a-b) x+ \) \( (a+b-c)=0 \) are rational.

Which is equivalent to \( \frac{x^{3}}{\sqrt{x}} \) ? A. \( x^{3 / 2} \) B. \( x^{2} \) C. \( x^{5 / 2} \) D. \( x^{7 / 2} \) E. \( x^{6} \)

(59.) \( a b-b^{2}, a^{2} b+b \) এর গসাগু কত?