Answer:
BD = √97 cm ≈ 9.849 cm
Step-by-step explanation:
Diagonal BD of rectangle ABCD is the hypotenuse of right triangle ABD. Opposite sides of the rectangle are the same length, so we have ...
AB = 4 cm
AD = 9 cm
The sides are related to the diagonals by the Pythagorean theorem.
<h3>Pythagorean theorem</h3>
The Pythagorean theorem tells you the relation between sides and hypotenuse of a right triangle:
AB² +AD² = BD²
4² +9² = BD² = 16 +81 . . . . . evaluating the squares
BD = √97 . . . . . take the square root
The length of BD is √97 cm, about 9.849 cm.
Answer:
it's 5 because 20 -15 is 5
Answer:
8
Step-by-step explanation:
0) the basic formula is: L=v*t, where L - distance, v - speed/velocity; t - time;
1) if the person's speed in still water is 'v' and the speed of water is 5 (according to the condition), then the upstream speed is 'v-5' and the downstream speed is 'v+5';
2) according to the condition the upstream time and the downstream time are the same, it means t₁=t₂=t, where t₁=upstream time and t₂=downstream time;
3) according to the items above it is possible to make up the equation of the upstream travel: t(v-5)=3; ⇒ t=3/(v-5);
4) according to the items above it is possible to make up the equation of the downstream travel: t(v+5)=13; ⇒ t=13/(v+5);
5) if t=3/(v-5) and t=13/(v+5), then
