Answer:
the two numbers are 151 and 66
Step-by-step explanation:
x+y =217
x-y = 85
add the two equations
x+y =217
x-y = 85
-------------
2x = 302
divide by 2
2x/2 = 302/2
x = 151
now find y
x+y =217
151+y =217
subtract 151 from each side
y = 217-151
y =66
. Lisa's dog has 4 squeaky toys
. the squeaky toys are 2/3 of all the dog's toys
. let <em>x</em> be number of all dog toys
<em>make an equation</em>
(2/3)<em>x</em> = 4 <em>← solve</em>
x=6
<em>check</em>
2/3 × 6 = 4
<u>Lisa's Dog has 6 toys in all</u>
Answer:
A. 25%
25% is equivalent to 1/4 and when you multiply 75 by 4 you get 300. Which means 75 is equivalent to 1/4 and 1/4 is equivalent to 25%. So the answer is 25%. I'm so sorry if this explanation is bad
Let x and y be the 2 parts of 15 ==> x + y=15 (given)
Reciprocal of x and y ==> 1/x +1/y ==> 1/x + 1/y = 3/10 (given)
Let's solve 1/x + 1/y = 3/10 . Common denominator = 10.x.y (reduce to same denominator)
==> (10y+10x)/10xy = 3xy/10xy ==> 10x+10y =3xy
But x+y = 15 , then 10x+10y =150 ==> 150=3xy and xy = 50
Now we have the sum S of the 2 parts that is S = 15 and
their Product = xy =50
Let's use the quadratic equation for S and P==> X² -SX +P =0
Or X² - 15X + 50=0, Solve for X & you will find:
The 1st part of 15 is 10 & the 2nd part is 5
Add all the item together:
16 + 28 + 12 + 4
=60 total items