Answer:
AC ≈ 12.9 cm
Step-by-step explanation:
Using the ratio
sin40° = 
Multiply both sides by 20
20 × sin40° = b, hence
AC = b = 20 × sin40° ≈ 12.9
Answer: ∠DOB: 48°
Step-by-step explanation:
1. we need an equation first. the sum of all angles (108°, n°, 2n°) is equal to 180°. we can depict this with the equation: 108°+2n°+n°=180°
2. now we can solve for the missing variable, n.
108°+3n°=180° → subtract both sides by → 3n°=72° → divide both sides by 3 → n=24°
3. now that we know that n=24°, we can solve the value of ∠DOB. we can see that ∠DOB is 2n° which we just plug the number we got for n into the equation. 2*24=48° meaning ∠DOB is 48°
hope this heped! ♡
The answer is 0.154 m
Step 1. Calculate the volume of gasoline tank (V) using the known mass (m) and density of gasoline (D).
D = m/V
⇒ V = m/D
D = 719.7 kg/m³
m = 45.0 kg
V = 45.0 kg/719.7 kg/m³ = 0.0625 m³
Step 2. Calculate the depth of the tank (d) using the known volume (V) of gasoline and width (w) and length (l) of the tank:
V = d * w * l
0.0625 = d * 0.900 * 0.450
0.0625 = d * 0.405
d = 0.0625 / 0.405
d = 0.154 m
10%of 710 is 71
now we have 710-71=639
Answer:
Step-by-step explanation:
Both expressions are examples of the <em>distributive property</em>, which basically says "if I have <em>this </em>many groups of some size and <em>that</em> many groups of the same size, I've got <em>this </em>+ <em>that</em> groups of that size altogether."
To give an example, if I've got <em>3 groups of 5 </em>and <em>2 groups of 5</em>, I've got 3 + 2 = <em>5 groups of 5 </em>in total. I've attached a visual from Math with Bad Drawings to illustrate this idea.
Mathematically, we'd capture that last example with the equation
. We can also read that in reverse: 3 + 2 groups of 5 is the same as adding together 3 groups of 5 and 2 groups of 5; both directions get us 8 groups of 5. We can use this fact to rewrite the first expression like this: 
.
This idea extends to subtraction too: If we have 3 groups of 4 and we take away 1 group of 4, we'd expect to be left with 3 - 1 = 2 groups of 4, or in symbols: 
. When we start with two numbers like 15 and 10, our first question should be if we can split them up into groups of the same size. Obviously, you could make 15 groups of 1 and 10 groups of 1, but 15 is also the same as <em>3 groups of 5</em> and 10 is the same as <em>2 groups of 5</em>. Using the distributive property, we could write this as 
, so we can say that 
.
