All categories

3 years ago

Jenna and Heidi together have $60. Jenna has $9 more than twice Heidi’s amount. How much money does each have?

Mathematics

1 answer:

Marina86 [1]3 years ago

4 0

Jenna has $43 and Heidi has $17.

Step-by-step explanation:

Total amount = $60

Let,

Amount of Jenna = x

Amount of Heidi = y

According to given statement;

x+y=60 Eqn 1

x=2y+9 Eqn 2

Putting value of Eqn 2 in Eqn 1;

$(2y+9)+y=60\\2y+9+y=60\\3y=60-9\\3y=51$

Dividing both sides by 3,

$\frac{3y}{3}=\frac{51}{3}\\y=17\\$

Putting y=17 in Eqn 2

$x=2(17)+9\\x=34+9\\x=43$

Jenna has $43 and Heidi has $17.

Keywords: linear equations, substitution method

Learn more about substitution method at:

#LearnwithBrainly

You might be interested in

Find the slope of the line that passes through (10,8) and (8,0).

N76 [4]

Answer:

The slope of the line that passes through points ( -10, -8 ) and ( -8, -16 ) is -4.

Explanation:

Points given = ( -10, -8) and ( -8, -16)

Slope = ?

( -10, -8 ) : x1 = -10 and y1 = -8

( -8, -16 ) : x2 = -8 and y2 = -16

We know,

slope = y2 - y1 / x2 - x1

Slope = -16 - ( -8) / -8 - (-10)

slope = -16 + 8 / -8 + 10

slope = -8 / 2

slope = -4

Therefore, slope of the line that passes through points ( -10, -8 ) and ( -8, -16 ) is -4.

Step-by-step explanation:

3 0

3 years ago

Mountain Ski Corp. was set up to take large risks and is willing to take the greatest risk possible. Lakeway Train Co. is more t

nasty-shy [4]

A-2: Project D.

b: Project A.

Not sure about a-1, hope I helped.

7 0

3 years ago

Which definite integral approximation formula is this: the integral from a to b of f(x)dx ≈ (b-a)/n * [<img src="https://tex.z-d

Stella [2.4K]

The answer is most likely A.

The integration interval [a, b] is split up into n subintervals of equal length (so each subinterval has width (b - a)/n, same as the coefficient of the sum of y terms) and approximated by the area of n rectangles with base (b - a)/n and height y.

n subintervals require n + 1 points, with

x₀ = a

x₁ = a + (b - a)/n

x₂ = a + 2(b - a)/n

and so on up to the last point x = b. The right endpoints are x₁, x₂, … etc. and the height of each rectangle are the corresponding y 's at these endpoints. Then you get the formula as given in the photo.

• "Average rate of change" isn't really relevant here. The AROC of a function G(x) continuous* over an interval [a, b] is equal to the slope of the secant line through x = a and x = b, i.e. the value of the difference quotient

(G(b) - G(a) ) / (b - a)

If G(x) happens to be the antiderivative of a function g(x), then this is the same as the average value of g(x) on the same interval,

$g_{\rm ave}=\dfrac{G(b)-G(a)}{b-a}=\dfrac1{b-a}\displaystyle\int_a^b g(x)\,\mathrm dx$

(* I'm actually not totally sure that continuity is necessary for the AROC to exist; I've asked this question before without getting a particularly satisfying answer.)

• "Trapezoidal rule" doesn't apply here. Split up [a, b] into n subintervals of equal width (b - a)/n. Over the first subinterval, the area of a trapezoid with "bases" y₀ and y₁ and "height" (b - a)/n is

(y₀ + y₁) (b - a)/n

but y₀ is clearly missing in the sum, and also the next term in the sum would be

(y₁ + y₂) (b - a)/n

the sum of these two areas would reduce to

(b - a)/n = (y₀ + 2 y₁ + y₂)

which would mean all the terms in-between would need to be doubled as well to get

$\displaystyle\int_a^b f(x)\,\mathrm dx\approx\frac{b-a}n\left(y_0+2y_1+2y_2+\cdots+2y_{n-1}+y_n\right)$

7 0

3 years ago

The equation of line s is y=1/3x-3. The equation of line t is y=-x+5. the equations of line s and t form a system of equations.

BigorU [14]

Y=-x+5

-x+5=1/3x-3
-x+8=1/3x
8=4/3x
6=x

y=-6+5
y=-1

C.

6 0

3 years ago

The question is in the picture

yawa3891 [41]

Answer: May you show the angle we are supposed to solve? its a bit unclear. or can you explain the angle to us?

Step-by-step explanation:

6 0

3 years ago