All categories

3 years ago

If (3)x+y = 81 and (81)x-y = 3 find the values of x and y.

1 answer:

7 0

You have to isolate the variables meaning you have to do the opposite of multiply 81 you have to divide 3/81: x and y for both sides will be the same thing

You might be interested in

A formula for the perimeter of a rectangle is P=2(l+w), where P is the perimeter, l is the length, and w is the width.

NNADVOKAT [17]

1408 because you need to multiply it to get the perimeter

7 0

2 years ago

Hay dos veces la cantidad de manzanas que naranjas en un puesto de frutas. Después de que se vendieron 15 naranjas, hay tres vec

Nastasia [14]

Answer:

Step-by-step explanation:

4 0

3 years ago

A. A man weighs 185 lb. What is his mass in grams?

zalisa [80]

Answer: About 83915 grams

.............................

8 0

2 years ago

Find the volume of the wedge with vertices at points (0,0,0), (1,0,0), (0,1,0), (0,0,1) by integrating the area of cross-section

Angelina_Jolie [31]

Answer:

V = 1/6 cubic units

Step-by-step explanation:

Applying the concept of integrals for volume calculation:

$V = \int\limits^b_a {S(x)} \, dx$ (1)

V = volume of the solid bounded by x = a and x = b

S(x) = cross section area of the solid, perpendicular to the x axis

From the figure we have that S is the area of a triangle that has base Z and height Y

Area of the triangle = $S(x)=\frac{y(x)*z(x)}{2}$ (2)

Calculation of y(x) and z(x)

We apply the equation of the point-slope line (plane xy):

Slope = $m = \frac{y_{2} - y_{1} }{x_{2} - x_{1}}$ (3)

Equation of the line = $y - y_{1} =m(x-x_{1} )$ (4)

Replacing the points (1,0) and (0,1) in (3):

$m=\frac{1-0}{0-1} =-1$

Replacing the point (1,0) and m = -1 in (4):

$y-0=(-1)(x-1)$

y(x) = -x + 1 (Line A-B) (5)

We apply the equation of the point-slope line (plane xz):

Slope = $m = \frac{z_{2} - z_{1} }{x_{2} - x_{1}}$ (6)

Equation of the line = $z - z_{1} =m(x-x_{1} )$ (7)

Replacing the points (1,0) and (0,1) in (6):

$m=\frac{1-0}{0-1} =-1$

Replacing the point (1,0) and m = -1 in (7):

$z-0=(-1)(x-1)$

z(x) = -x + 1 (Line A-C) (8)

Replacing (5) and (8) in (2)

$S(x) = \frac{(-x + 1) * (-x + 1)}{2} =\frac{(-x + 1)^{2} }{2}$ (9)

Replacing (9) in (1) and knowing that a = 0 and b = 1:

$V = \int\limits^1_0 {\frac{(-x + 1)^{2} }{2}} \, dx = \int\limits^1_0 {\frac{x^{2}-2x+1 }{2}} \, dx$

$V =\frac{1}{2} (\frac{x^{3} }{3} -2\frac{x^{2} }{2} +x)$ evaluated from x=0 to x=1

$V= \frac{1}{2} (\frac{1}{3} -1 +1) = \frac{1}{6}$

3 0

3 years ago

Help immediately please

Debora [2.8K]

Answer:

35,45,55 is not a triangle

Step-by-step explanation:

The three angles of a triangle add to 180

30+60+90 = 180

true

45+55+80 = 180

true

30+45+105 =180

true

35+45+55 =180

135 does not =180

false

4 0

3 years ago