Answer:
<em>m∠C = 30° </em>
Step-by-step explanation:
If ΔADB is an equilateral, then m∠A = m∠ADB = m∠DBA = 60°
If ΔDBC isosceles with DB ≅ BC, then m∠C = m∠BDC ;
m∠C + m∠BDC = m∠DBA = 60° ⇒ <em>m∠C = 30°</em>
I have no idea, someone help
By applying algebraic handling on the two equations, we find the following three <em>solution</em> pairs: x₁ ≈ 5.693 ,y₁ ≈ 10.693; x₂ ≈ 1.430, y₂ ≈ 6.430; x₃ ≈ - 0.737, y₃ ≈ 4.263.
<h3>How to solve a system of equations</h3>
In this question we have a system formed by a <em>linear</em> equation and a <em>non-linear</em> equation, both with no <em>trascendent</em> elements and whose solution can be found easily by algebraic handling:
x - y = 5 (1)
x² · y = 5 · x + 6 (2)
By (1):
y = x + 5
By substituting on (2):
x² · (x + 5) = 5 · x + 6
x³ + 5 · x² - 5 · x - 6 = 0
(x + 5.693) · (x - 1.430) · (x + 0.737) = 0
There are three solutions: x₁ ≈ 5.693, x₂ ≈ 1.430, x₃ ≈ - 0.737
And the y-values are found by evaluating on (1):
y = x + 5
x₁ ≈ 5.693
y₁ ≈ 10.693
x₂ ≈ 1.430
y₂ ≈ 6.430
x₃ ≈ - 0.737
y₃ ≈ 4.263
By applying algebraic handling on the two equations, we find the following three <em>solution</em> pairs: x₁ ≈ 5.693 ,y₁ ≈ 10.693; x₂ ≈ 1.430, y₂ ≈ 6.430; x₃ ≈ - 0.737, y₃ ≈ 4.263.
To learn more on nonlinear equations: brainly.com/question/20242917
#SPJ1
9 students
30% ends up being .3%, multiply .3% by 30 students which equals 9.
Answer:
16
Step-by-step explanation:
Start by adding 9 to both sides, obtaining: √(x + 9) = 5.
Square both sides, obtaining: x + 9 = 25.
Subtract 9 from both sides: x = 16
Note that √(16+9) - 9 = -4, as required.