Answer:
x = - 2
y = 6
Step-by-step explanation:
The best way to do this is to put - 3x in for y in the second equation.
4x - 2(-3x) = - 20 Watch the signs. You have 2 minus signs.
4x - - 6x = -20 Change - - 6x to 6x
4x + 6x = - 20 Add
10x = - 20 Divide by 10
x = -20/10
x = - 2
============================
Find y
y = - 3x
y = -3 * -2
y = 6
First you must find x in order to solve this question, unless you do not need to find out X.
Answer:
She could make 5 of each type.
Step-by-step explanation:
If x is the number of 0.5 pound hamburgers and y is the number of 0.25 pound hamburgers:
0.5x + 0.25y = 3.75
Divide through by 0.25:
2x + y = 15
Some whole numbers which fit this relation are x = 5 and y = 5.
2√72 / √8 ± √2
If the denominator is √8 + √2,
2√72 / √8 + √2
= 2√(2*2*2*3*3) / √(2*2*2) + √2
= 2*2*3√2 / 2√2 + √2
= 12√2 / 3√2
= 4
Answer:
11 of 20p, 22 of 10p and 33 of 5p
Step-by-step explanation:
Eva has 20p, 10p and 5p coins, total of £6.05 = 605p
Let 20p=x, 10p=y, 5p=z
<u>Then</u>:
- 20x + 10y + 5z = 605
- y : x = 2 : 1 ⇒ x= y/2
- y : z = 2 : 3 ⇒ z= 3y/2
<u>Rewriting the first equation considering next two:</u>
- 10y + 10y + 7.5y = 605
- 27.5y = 605
- y= 605/27.5
- y= 22
- x= y/2 = 22/2 = 11
- z = 3y/2 = 3*11 = 33
<u>Answer:</u> 11 of 20p coins, 22 of 10p coins and 33 of 5p coins