Answer:
x=14/5
Step-by-step explanation:
Group like terms
2x+8x+7=35
Add similar elements: 2x+8x=10x
10x+7=35
Subtract 7 from both sides:
10x+7−7=35−7
Simplify
10x=28
Divide both sides by 10
10x/10 =28/10
Simplify:
x=14/5
Answer:
Her error was multiplying numerator by numerator ( that is Quantity of Bone-shaped treats)
Step-by-step explanation:
Sarah's calculation
Let
x = cost of 12 Bone-shaped treats
Quantity of Bone-shaped treats : price
5 : 3.5 = 12 : x
(5/3.5) = (12/x)
Cross product
3.5x=60 (Here is her error)
x=17.14
Correct calculation
Quantity of Bone-shaped treats : price
5 : 3.5 = 12 : x
5 / 3.5 = 12 / x
Cross product
5 * x = 3.5 * 12
5x = 42
x = 42 / 5
= 8.4
x = $8.4
Her error was multiplying numerator by numerator ( that is Quantity of Bone-shaped treats)
Instead of multiplying Quantity of Bone-shaped treats by cost
Separate the vectors into their <em>x</em>- and <em>y</em>-components. Let <em>u</em> be the vector on the right and <em>v</em> the vector on the left, so that
<em>u</em> = 4 cos(45°) <em>x</em> + 4 sin(45°) <em>y</em>
<em>v</em> = 2 cos(135°) <em>x</em> + 2 sin(135°) <em>y</em>
where <em>x</em> and <em>y</em> denote the unit vectors in the <em>x</em> and <em>y</em> directions.
Then the sum is
<em>u</em> + <em>v</em> = (4 cos(45°) + 2 cos(135°)) <em>x</em> + (4 sin(45°) + 2 sin(135°)) <em>y</em>
and its magnitude is
||<em>u</em> + <em>v</em>|| = √((4 cos(45°) + 2 cos(135°))² + (4 sin(45°) + 2 sin(135°))²)
… = √(16 cos²(45°) + 16 cos(45°) cos(135°) + 4 cos²(135°) + 16 sin²(45°) + 16 sin(45°) sin(135°) + 4 sin²(135°))
… = √(16 (cos²(45°) + sin²(45°)) + 16 (cos(45°) cos(135°) + sin(45°) sin(135°)) + 4 (cos²(135°) + sin²(135°)))
… = √(16 + 16 cos(135° - 45°) + 4)
… = √(20 + 16 cos(90°))
… = √20 = 2√5
There would be 180 blue jeans. If you need any question how I got that answer, ask me.. :)
