1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
WITCHER [35]
3 years ago
13

Roxie is buying toys. 2 balls and 4 dolls cost $8.20. 3 balls and 1 doll cost $6.50. Write a system of equations to model this s

ituation.
Mathematics
1 answer:
Nadya [2.5K]3 years ago
5 0
X+z=thanks for points
You might be interested in
(a) Use the reduction formula to show that integral from 0 to pi/2 of sin(x)^ndx is (n-1)/n * integral from 0 to pi/2 of sin(x)^
Sedbober [7]
Hello,

a)
I= \int\limits^{ \frac{\pi}{2} }_0 {sin^n(x)} \, dx = \int\limits^{ \frac{\pi}{2} }_0 {sin(x)*sin^{n-1}(x)} \, dx \\

= [-cos(x)*sin^{n-1}(x)]_0^ \frac{\pi}{2}+(n-1)*\int\limits^{ \frac{\pi}{2} }_0 {cos(x)*sin^{n-2}(x)*cos(x)} \, dx \\

=0 + (n-1)*\int\limits^{ \frac{\pi}{2} }_0 {cos^2(x)*sin^{n-2}(x)} \, dx \\

= (n-1)*\int\limits^{ \frac{\pi}{2} }_0 {(1-sin^2(x))*sin^{n-2}(x)} \, dx \\
= (n-1)*\int\limits^{ \frac{\pi}{2} }_0 {sin^{n-2}(x)} \, dx - (n-1)*\int\limits^{ \frac{\pi}{2} }_0 {sin^n(x) \, dx\\


I(1+n-1)= (n-1)*\int\limits^{ \frac{\pi}{2} }_0 {sin^{n-2}(x)} \, dx \\
I= \dfrac{n-1}{n} *\int\limits^{ \frac{\pi}{2} }_0 {sin^{n-2}(x)} \, dx \\


b)
\int\limits^{ \frac{\pi}{2} }_0 {sin^{3}(x)} \, dx \\
= \frac{2}{3} \int\limits^{ \frac{\pi}{2} }_0 {sin(x)} \, dx \\
= \dfrac{2}{3}\ [-cos(x)]_0^{\frac{\pi}{2}}=\dfrac{2}{3} \\






\int\limits^{ \frac{\pi}{2} }_0 {sin^{5}(x)} \, dx \\
= \dfrac{4}{5}*\dfrac{2}{3} \int\limits^{ \frac{\pi}{2} }_0 {sin(x)} \, dx = \dfrac{8}{15}\\







c)

I_n=  \dfrac{n-1}{n} * I_{n-2} \\

I_{2n+1}=  \dfrac{2n+1-1}{2n+1} * I_{2n+1-2} \\
= \dfrac{2n}{2n+1} * I_{2n-1} \\
= \dfrac{(2n)*(2n-2)}{(2n+1)(2n-1)} * I_{2n-3} \\
= \dfrac{(2n)*(2n-2)*...*2}{(2n+1)(2n-1)*...*3} * I_{1} \\\\

I_1=1\\






3 0
3 years ago
2. Half of Robert's piece of wire is equal to of Maria's wire. The total length of their wires is 10 feet. How much longer is Ro
Aleonysh [2.5K]

Step-by-step explanation:

Given that,

Half of Robert's piece of wire is equal to of Maria's wire i.e.

\dfrac{R}{2}=M ....(1)

Total length of the wires = 10 feet

ATQ,

R+M=10 ....(2)

Use equation (1) in (2).

R+\dfrac{R}{2}=10\\\\\dfrac{3R}{2}=10\\\\R=\dfrac{20}{3}\\\\R=6.67\ ft

So,

M=\dfrac{6.67}{2}\\\\M=3.33\ ft

Hence, this is the required solution.

6 0
3 years ago
-0.2x^2+0.9x+0.6=y<br>What's the vertex form for this equation?​
hjlf

Answer:   y = -0.2(x - 2.25)² + 1.6125

<u>Step-by-step explanation:</u>

y = -0.2x^2 + 0.9x + 0.6\\\\y - 0.6 = -0.2x^2 + 0.9x\\\\y - 0.6 =-0.2(x^2-4.5x)\\\\y-0.6+\underline{(-0.2)(2.25)^2}=-0.2(x^2-4.5x+\underline{2.25^2})\\\\y-0.6-1.0125=-0.2(x-2.25)^2\\\\y-1.6125=-0.2(x-2.25)^2\\\\y=-0.2(x-2.25)^2+1.6125

6 0
3 years ago
Anyone know how to solve this?? Number 5!!
iragen [17]
P=6+1+2
6+1+2=9 x 3= 27
8 0
3 years ago
A grocery store sells avocados for $1.25 each. The graph shows the cost for different numbers of avocados.
Aleksandr [31]
I don’t know if this is right or not so, sorry if it’s wrong ;-;

1,2,3,4,5 = independent

c=1.25a = neither

$1.25, $2.50, $3.75, $5.00, $6.25 = dependent

Number of avocados = independent

Cost of avocados = dependent

If this is right then I’ll put the explanation in the comments, again sorry if it isn’t.
5 0
3 years ago
Other questions:
  • Help. divide and simplify(104i)/(3+i) express a in a + bi form
    13·1 answer
  • The half life of Pb-210 is 22 years. A decayed animal shows 16% of the original Pb-210 remains; how long has the animal been dec
    7·1 answer
  • p: 3 is an odd number q: 9 is an even number Which of the following statements is false? p ∨ q p ∧ q q → p
    10·2 answers
  • How to square root this equation
    12·1 answer
  • Find the x-intercept of the parabola with vertex (-3,16 and y-intercept (0,-20
    14·1 answer
  • Square roots of 263 by division method ​
    5·1 answer
  • 100 point giveaway<br> answer anything idc<br> NO LINKS
    5·2 answers
  • Whats the common ratio of the geometric sequence 6, 36, 216,
    9·1 answer
  • Please help! Will give brainliest, pls no fake answers or links. :)
    6·2 answers
  • What is the answer to 1-x=16-4x and how did u get it?
    7·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!