All categories

2 years ago

19. Seja 17x 51y+ 102. Qual é o valor de 9x 27y ? (A) 54 (B) 36 (C) 34 (D) 18 (E) indeterminado

Mathematics

1 answer:

lilavasa [31]2 years ago

4 0

Pergunta correta:

Seja 17x + 51y = 102. Qual é o valor de 9x + 27a? (A) 54 (B) 36 (C) 34 (D) 18 (E) indeterminado

Resposta: A) 54

Explicação passo a passo:

17x + 51y = 102 - - - - equação 1

Divulgue até 17

x + 3y = 6 - - - - - - - Equação 2

9x + 27y - - - - - - - equação 3

Comparando as equações 2 e 3

(Equação 3) = 9 × (equação 2)

Isso é, 9x + 27y = 9 × (x + 3y = 6)

9x + 27y = 9x + 27y = 54

Portanto ; 9x + 27y = 54

You might be interested in

The batting Wang Xiu Ying uses to fill quilts has a thermal conductivity rate of 0.030.030, point, 03 watts (\text{W})(W)left pa

alexgriva [62]

Answer:

0.0003W/cm°C

Step-by-step explanation:

The question is not properly written. Here is the correct question.

The batting wang xiu ying uses to fill quilts has a thermal conductivity rate of 0.03 watts (W) per meter(m) per degree celsius. what is the batting thermal conductivity when w/cm•c

Given the thermal conductivity in W/m°C to be 0.03W/m°C

We are to rewrite the value in W/cm°C

The difference is the unit. The only thing we need to do is to simply convert the unit (metres) in W/m°C to centimeters (cm)

Since 100cm = 1m, 0.03W/m°C can be expressed as shown below;

= 0.03W/m°C

= 0.03 × W/1m×°C

Note that 1m = 100cm, substituting this conversion into the expression, it will become;

= 0.03 × W/100cm × °C

= 0.03/100 × W/cm°C

= 0.0003W/cm°C

Hence the battling thermal conductivity in W/cm°C is 0.0003W/cm°C

4 0

2 years ago

A skating rink charges $0.75 to rent skates and $1.25 per hour to skate. How many hours did Penny skate if she was charged $4.50

ArbitrLikvidat [17]

She was skating for 3 hours.

4 0

2 years ago

3. Jacob and Sarah are saving money to go on a trip. They need at least $1975 in order to go. Jacob mows lawns and Sarah walks d

kvv77 [185]

1. The total must be at least $1975: $25x+15y \geq \$1975$

2. Dog walks is no more than 4 times lawns: $y \leq 4x$

3. At least 50 dog walks: $y \geq 50$

5 0

2 years ago

The variable complex number z is given by z=1+cos 2θ+isin2θ,where θ takes all values in the interval −1/2π<θ<1/2π

FinnZ [79.3K]

The given complex number is
z = 1 + cos(2θ) + i sin(2θ), for -1/2π < θ < 1/2π

Part (i)
Let V = the modulus of z.
Then
V² = [1 + cos(2θ)]² + sin²(2θ)
= 1 + 2 cos(2θ) + cos²2θ + sin²2θ

Because sin²x + cos²x = 1, therefore
V² = 2(1 + cos2θ)

Because cos(2x) = 2 cos²x - 1, therefore
V² = 2(1 + 2cos²θ - 1) = 4 cos²θ
Because -1/2π < θ < 1/2π,
V = 2 cosθ PROVEN

Part ii.
1/z = 1/[1 + cos2θ + i sin 2θ]
$\frac{1}{z} = \frac{(1+cos2\theta - i\, sin2\theta)}{(1 + cos 2\theta + i\, sin 2\theta)(1+cos2\theta - i \,sin2\theta)}\\ = \frac{1+cos2\theta - i \,sin 2\theta}{(1+cos2\theta)^{2} + sin^{2}2\theta}$

The denominator is
$(1+cos2\theta)^{2}+sin^{2}2\theta \\ = 1+2cos2\theta+cos^{2}2\theta+sin^{2}2\theta \\ =2cos2\theta+2 \\ = 2(1+cos2\theta)$

Therefore
$\frac{1}{z} = \frac{1}{2} -i \frac{sin2\theta}{2(1+cos2\theta)}$

The real part of 1/ = 1/ (constant).

6 0

2 years ago

Tim has an after-school delivery service that he provides for several small retailers in town. He uses his bicycle and charges $

nlexa [21]

Answer:

Step-by-step explanation:

Given that

For delivery within $1\frac{1}2$ mi, charges = $1.25