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2 years ago

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If x/0.5 + y/0.2 = 18, where x and y are positive integers, then what is the value of x ?

1 answer:

dem82 [27]2 years ago

7 0

An equation without exponents and two variables, is typically a straight line. All the points on the line with integer coordinates are solutions of the equation. Since x and y have to be positive as well, there aren't that many solutions.

Let's see where the line crosses the x-axis, it is where y=0:

x/0.5 + 0 = 18, so x=9 at the intercept. y=0 there, so this is a point on the line, but not a solution to the question (y was supposed to be positive).

Possible values for x are thus limited to 1,2,3,4,5,6 and 7. You can try them all (ie., solve the equation with them) and see for which x values the y is also positive and integer.

You will find that x=4, y=2 is the only pair that satisfies these conditions.

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Mariel brought 48 brownies to school for a class party. The class ate 5/6 of the brownies, and Mariel brought the rest home. How

Likurg_2 [28]

The number of brownies Mariel brought home is 8

<u>Explanation:</u>

Given:

Total number of brownies, n = 48

Class ate = $\frac{5}{6} X 48$

= 40

Mariel brought rest of the brownies home.

So, the number of brownies Mariel brought home = 48 - 40

= 8

3 0

3 years ago

Find the product: <br><br>(i) (5 – 2x) (3 + x)

Ilya [14]

<h2><u>Solution</u>:</h2>

$\:$

$\large\red{ \longrightarrow} \pmb{ \sf{(5 – 2x) (3 + x)}}$

$\:$

$\mapsto \: \: \: \sf{5(3 + x) – 2x(3 + x)}$

$\:$

$\mapsto \: \: \: \sf{(5 × 3) + (5 × x) – (2x × 3) – (2x × x)}$

$\:$

$\leadsto \: \: \: \sf{ 15 + 5x – 6x – 2x ^{2} }$

$\:$

hope it helps!! :)

7 0

2 years ago

Read 2 more answers

Joaquin buys 3 packs light bulbs. Each pack contains 12 lights bulbs. After changing the bulbs in his house he has 15 light bulb

denpristay [2]

Answer:

Step-by-step explanation:

3x12=36 light bulbs total

36-15=21 used light bulbs with 15 left unused

8 0

3 years ago

What is the solution to the system of equations?

aev [14]

Answer:

B

Step-by-step explanation:

Given the 2 equations

y = 2x + 6 → (1)

y = x + 2 → (2)

Substitute y = 2x + 6 into (2)

2x + 6 = x + 2 ( subtract x from both sides )

x + 6 = 2 ( subtract 6 from both sides )

x = - 4

Substitute x = - 4 into either of the 2 equations and evaluate for y

Substituting into (2)

y = - 4 + 2 = - 2

solution is (- 4, - 2 ) → B

7 0

2 years ago

NO LINKS!! Please help me with this problem

Reika [66]

Answer:

23.1 years (nearest tenth)

Step-by-step explanation:

<u>Compound Interest Formula</u>

$\large \text{$ \sf A=P\left(1+\frac{r}{n}\right)^{nt} $}$

where:

A = final amount
P = principal amount
r = interest rate (in decimal form)
n = number of times interest applied per time period
t = number of time periods elapsed

Given:

A = $1200
P = $600
r = 3% = 0.03
n = 12 (as compounded monthly)
t = years

Substitute the given values into the formula and solve for t:

$\implies \sf 1200=600\left(1+\dfrac{0.03}{12}\right)^{12t}$

$\implies \sf 1200=600\left(1.0025\right)^{12t}$

$\implies \sf \dfrac{1200}{600}=\left(1.0025\right)^{12t}$

$\implies \sf 2=\left(1.0025\right)^{12t}$

Take natural logs:

$\implies \sf \ln 2=\ln \left(1.0025\right)^{12t}$

$\implies \sf \ln 2=12t\ln \left(1.0025\right)$

$\implies t=\dfrac{ \ln 2}{12 \ln (1.0025)}$

$\implies t=23.13377513...$

$\implies t=23.1\: \sf years \:\:(nearest\:tenth)$

The money will double in value in approximately $\boxed{\sf 23.1}$ years.

3 0

1 year ago

Read 2 more answers