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Tobeg says the equation 3x + 2y= 270 and y=4/5x + 20 intersect at the point (50,60) is this true how do you know

il63 [147K]

ANSWER

Yes it is very true

<u>EXPLANATION</u>

If the two equations intersect at $(50,60)$ then this point must satisfy the two equations.

$3x+2y=270---(1)$

We substitute $(50,60)$ in to erquation (1)

$3(50)+2(60)=270$

$150+120=270$

$270=270$

$y=\frac{4}{5}x+20 ---(2)$

We now substitute $(50,60)$ in to erquation (2) also

$60=\frac{4}{5}(50)+20$

$60=40+20$

$60=60$

Since the point satisfy all the two equations, it is true that they intersect at $(60,50)$

3 0

3 years ago

Simplify 42 ⋅ 48 thanks

Andreyy89

42•48=2,016. Hope this helped!

4 0

3 years ago

The measurenicnt of the circumference of a circle is found to be 56 centimeters. The possible error in measuring the circumferen

BartSMP [9]

Answer:

(a) Approximate the percent error in computing the area of the circle: 4.5%

(b) Estimate the maximum allowable percent error in measuring the circumference if the error in computing the area cannot exceed 3%: 0.6 cm

Step-by-step explanation:

(a)

First we need to calculate the radius from the circumference:

$c=2\pi r\\r=\frac{c}{2\pi } \\c=8.9 cm$

I leave only one decimal as we need to keep significative figures

Now we proceed to calculate the error for the radius:

$\Delta r=\frac{dt}{dc} \Delta c\\\\\frac{dt}{dc} = \frac{1}{2 \pi } \\\\\Delta r=\frac{1}{2 \pi } (1.2)\\\\\Delta r= 0.2 cm$

$r = 8.9 \pm 0.2 cm$

Again only one decimal because the significative figures

Now that we have the radius, we can calculate the area and the error:

$A=\pi r^{2}\\A=249 cm^{2}$

Then we calculate the error:

$\Delta A= (\frac{dA}{dr} ) \Delta r\\\\\Delta A= 2\pi r \Delta r\\\\\Delta A= 11.2 cm^{2}$

$A=249 \pm 11.2 cm^{2}$

Now we proceed to calculate the percent error:

$\%e =\frac{\Delta A}{A} *100\\\\\%e =\frac{11.2}{249} *100\\\\\%e =4.5\%$

(b)

With the previous values and equations, now we set our error in 3%, so we just go back changing the values:

$\%e =\frac{\Delta A}{A} *100\\\\3\%=\frac{\Delta A}{249} *100\\\\\Delta A =7.5 cm^{2}$

Now we calculate the error for the radius:

$\Delta r= \frac{\Delta A}{2 \pi r}\\\\\Delta r= \frac{7.5}{2 \pi 8.9}\\\\\Delta r= 0.1 cm$

Now we proceed with the error for the circumference:

$\Delta c= \frac{\Delta r}{\frac{1}{2\pi }} = 2\pi \Delta r\\\\\Delta c= 2\pi 0.1\\\\\Delta c= 0.6 cm$

5 0

3 years ago

Wally wants to determine the height of a statue that casts a 164-inch shadow by comparing it to his own height and shadow length

nataly862011 [7]

We have been given that Wally wants to determine the height of a statue that casts a 164-inch shadow by comparing it to his own height and shadow length. Wally is 68 inches tall, casts a shadow that is 41 inches in length.

We will use proportions to solve for the height of the statue because proportions state that ratio between two proportional quantities is same.

$\frac{\text{Height of statue}}{\text{Shadow of statue}}=\frac{\text{Height of Wally}}{\text{Shadow of Wally}}$

Upon substituting our given values in above equation, we will get:

$\frac{\text{Height of statue}}{\text{164 cm}}=\frac{\text{68 inch}}{\text{41 inch}}$

$\frac{\text{Height of statue}}{\text{164 cm}}\times \text{164 cm}=\frac{\text{68 inch}}{\text{41 inch}}\times \text{164 cm}$

$\text{Height of statue}=\frac{\text{68 inch}}{1}\times 4$

$\text{Height of statue}=272\text{ inches}$

Therefore, the height of the statue is 272 inches.

5 0

2 years ago

What is 4x9.4 SHOW YOUR WORK!!!

Anettt [7]

Answer:

37.6

Step-by-step explanation:

Multiply the numbers

8 0

2 years ago