We can write out a formula in order to solve this. Since sum represents addition, if x represents the unknown number, we can write the formula: x+51=-21. Then, to solve for x, you would subtract 51 from both sides to get x=-72 which is the final answer.
Answer:
perimeter of ΔDEF ≈ 32
Step-by-step explanation:
To find the perimeter of the triangle, we will follow the steps below:
First, we will find the length of the side of the triangle DE and FF
To find the length DE, we will use the sine rule
angle E = 49 degrees
e= DF = 10
angle F = 42 degrees
f= DE =?
we can now insert the values into the formula
=
cross-multiply
f sin 49° = 10 sin 42°
Divide both-side by sin 49°
f = 10 sin 42° / sin 49°
f≈8.866
which implies DE ≈8.866
We will now proceed to find side EF
To do that we need to find angle D
angle D + angle E + angle F = 180° (sum of interior angle)
angle D + 49° + 42° = 180°
angle D + 91° = 180°
angle D= 180° - 91°
angle D = 89°
Using the sine rule to find the side EF
angle E = 49 degrees
e= DF = 10
ange D = 89 degrees
d= EF = ?
we can now proceed to insert the values into the formula
=
cross-multiply
d sin 49° = 10 sin 89°
divide both-side of the equation by sin 49°
d= 10 sin 89°/sin 49°
d≈13.248
This implies that length EF = 13.248
perimeter of ΔDEF = length DE + length EF + length DF
=13.248 + 8.866 + 10
=32.144
≈ 32 to the nearest whole number
perimeter of ΔDEF ≈ 32
B is the answer
i simplified the theorem, but i hope this makes sense!
To add monomials, you have to look at the variables that are accompanied by their coefficients. In the given problem, (–4c2 + 7cd + 8d) + (–3d + 8c2 + 4cd), you can combine both cd ut nt cd and c² and cd and d and d and c² because they have different variables.
<span>(–4c2 + 7cd + 8d) + (–3d + 8c2 + 4cd)
(-4c</span>² + 8c²) + (7cd + 4cd) + (8d - 3d)
4c² + 11cd + 5d
