Answer:
Not that I'm a chemistry expert but mathematically,The total weight of the bar is directly proportional to the known weight of the bar and the given percentage. I worked it out and found that the the total weight of the bar is 30 ounces. This is how I did it
Step-by-step explanation:
80:24
100:n
80(n)=100×24
A little equation and after it's solve the variable (n) will be equal to 30
The unit is added after calculations so that's how the answer is <em><u>3</u></em><em><u>0</u></em><em><u> </u></em><em><u>oun</u></em><em><u>ces</u></em>
Answer:
(1)
Donna = Pounds 180
Kyra = Pounds 240
(2)
Kelly = Pounds 225
Nelly = Pounds 175
Step-by-step explanation:
(1)
Donna = x
Kyra = x + 60
If Donna spends 1/3 of her money she is left with 2/3 of her money;
2/3 x
Kyra now has twice as much money as Donna can be represented as;
X + 60 = 2 * 2/3 x
X + 60 = 4/3 x
(x + 60)3 = 4x
3x + 180 = 4x
180 = 4x – 3x
180 = x
Donna = 180
Kyra = 180 + 60 = 240
(2)
Kelly = x
Ned = y
Kelly spends 40% of her money. Therefore he is left with 60%;
60/100 x
Nelly spends Euros 40 of his money. Therefore he is left with;
y- 40
If they now have the same amount of money;
60/100 x = y – 40
3/5 x = y – 40
3x = 5y – 200
3x – 5y = -200
Remember Kelly & Ned has Euros 400 in total;
x + y = 400
Now we can solve the simultaneous equation by substitution;
x + y= 400
3x – 5y = -200
3x + 3y = 1200
-
3x – 5y = - 200
=
8y = 1400
Y = 175
X = 225
Kelly = 225
Nelly = 175
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<h3>Given Equation:</h3>
x = 7 + 3y
or, x - 3y - 7 = 0 ........ (i)
5x + 6y = 14
or, 5x + 6y - 14 = 0 .........(ii)
<h3>To Find:</h3>
The value of x and y.
<h3>Solution:</h3>
By dividing eq. ii by 2, we get
5/2x + 3y - 7 = 0 ........ (iii)
By adding eq. i and eq. iii, we get
15/2x = 0
or, <u>x = 0</u> ........(iv)
By putting eq.(iv) in eq. (i), we get
0 - 3y - 7 = 0
or, -3y = 7
or, <u>y = </u><u>-</u><u>7/</u><u>3</u>
<h2>Answer: ( 0, -7/3 )</h2>
The value of x and y is 0 and -7/3 respectively.
Answer: (x+2)*(x-4)*(x+21) = 0 has "many" solutions
Step-by-step explanation: (x+2) = 0 only has one solution.
(x+2)*(x-4) = 0 has two solutions, -2 and 4
(x+2)*(x-4)*(x+21) = 0 has three solutions, -2, 4, and -21, etc
If "many" means more than three, then add another (x+XX) term. A quadratic equation generally has two solutions.
