| u | = √(2² + (-1²)) = √5
| v | = √ ( 1² + (-8)² = √65
cos (u,v) = ( u * v ) / (| u | * | v |) =
(2 * 1 + ( -1 ) * ( - 8 )) / √5 √ 65 = (2 + 8) / √5 √65 = 10 / (√5 √ 65 )
The length of a larger diagonal:
d 1² = | u |² + 2 |u| |v| + | v |² = 5 + (2 √5 √65 * 10 / √5 √65 )+65
d 1² = 70 + 20 = 90
d 1 = √ 90 = 3√10
d 2² = 70 - 20 = 50
d 2 = √50 = 5√2
Answer:
The lengths of the diagonals are: 3√10 and 5√2 .
To find the unit rate you do
$1.39/8 oz.=.17
Then, you multiply the unit rate by the ounces
.17 * 14 oz. = $2.43
Answer:
I believe its C?
Step-by-step explanation:
Remark
This may be a little confusing, but because they are travelling in opposite directions, the distances add when you want to get how far apart they are.
d1 + d2 = 1541
Equation
Let the time this happens = t
d1 = 323*t
d2 = 347*t
323*t + 347*t = 1541 Combine like terms on the left.
670t = 1541 Divide by 670
t = 1541/670
t = 2.3 hours pass before the distance of 1541 miles are between the two planes. You might need the answer to be 2 hours 18 minutes.
