Question

Calcule o valor numérico da expressão algébrica (2a+ b-c) em cada caso.

a) a=1 b=0 c=1

b)a=2 b= 5 c=3

c) a=4 b=9 c=7

d)a=1/2 b=4/5 c=8/10

e) a=4/3 b=4/5 c= 8/10

f)a=0,23 b=0,64 c)1,00

g)a=45,54 b=0,89 c=0,431​

Answer 1

Resposta:

(2a + b - c)

a) a = 1; b = 0; c = 1

2.(1) + 0 - 1

2 - 1

1

b) a=2; b= 5; c=3

2.(2) + 5 - 3

4 + 5 - 3

6

c) a=4; b=9; c=7

2.(4) + 9 - 7

8 + 9 - 7

10

d) a = $\frac{1}{2}$; b = $\frac{4}{5}$; c = $\frac{8}{10}$

2.$\frac{1}{2}$ +  $\frac{4}{5}$ - $\frac{8}{10}$

1 + $\frac{4}{5}$ - $\frac{8}{10}$

$\frac{10 + 8 + 8}{10}$

$\frac{26}{10} = \frac{13}{5}$

e) a = $\frac{4}{3}$; b = $\frac{4}{5}$; c = $\frac{8}{10}$

2.$\frac{4}{3}$ +  $\frac{4}{5}$ - $\frac{8}{10}$

$\frac{8}{3}$ + $\frac{4}{5}$ - $\frac{8}{10}$

$\frac{80 + 24 + 24}{30}$

$\frac{128}{30} = \frac{64}{15}$

f) a=0,23; b=0,64; c)1,00

2.(0,23) + 0,64 - 1,00

0,46 + 0,64 - 1

0,10

g) a=45,54; b=0,89; c=0,431​

2.(45,54) + 0,89 - 0,431

91,08 + 0,89 - 0,431

91,539