Answer:
4x-15
Step-by-step explanation
You just multiply -5 and -3 to simplify this.
Answer:
If B is between A and C, AB = x, BC = 2x + 2, and AC = 14, find the value of x. Then find AB and BC.
Step-by-step explanation:
AB=x
BC = 2x + 2BC=2x+2
AC =14AC=14
Required
Determine x, AB and BC.
Since B is between A and C;
AB + BC = ACAB+BC=AC
Substitute x for AB; 2x + 2 for BC and 14 for AC
x + 2x + 2 = 14x+2x+2=14
3x + 2 = 143x+2=14
Collect Like Terms
3x = 14 - 23x=14−2
3x = 123x=12 '
x = \frac{12}{3}x=
3
12
x = 4x=4
Substitute 4 for x in
AB = xAB=x
BC = 2x + 2BC=2x+2
AB = 4AB=4
BC = 2(4) + 2BC=2(4)+2
BC = 8 + 2BC=8+2
BC = 10BC=10
Answer:
b. 1
Step-by-step explanation:
Step 1: Define
y(x) = 4x
y(x) = 4
Step 2: Substitute and Evaluate
4 = 4x
x = 1
Answer:
300 doors.
Step-by-step explanation:
1.5 minutes for 1 door.
7.5 hours for 300 doors.
7.5 hours = 450 minutes.

Answer:
24.5 unit²
Step-by-step explanation:
Area of ∆
= ½ | x₁(y₂ - y₃) + x₂(y₃ - y₁) + x₃(y₁ - y₂) |
= ½ | (-1)(3 -(-4)) + 6(-4 -3) + (-1)(3 - 3) |
= ½ | -7 - 42 |
= ½ | - 49 |
= ½ (49)
= 24.5 unit²
<u>Method 2:</u>
Let the vertices are A, B and C. Using distance formula:
AB = √(-1-6)² + (3-3)² = 7
BC = √(-6-1)² + (-4-3)² = 7√2
AC = √(-1-(-1))² + (4-(-3))² = 7
Semi-perimeter = (7+7+7√2)/2
= (14+7√2)/2
Using herons formula:
Area = √s(s - a)(s - b)(s - c)
here,
s = semi-perimeter = (14 + 7√2)/2
s - a = S - AB = (14+7√2)/2 - 7 = (7 + √2)/2
s - b = (14+7√2)/2 - 7√2 = (14 - 7√2)/2
s - c = (14+7√2)/2 - 7 = (7 + √2)/2
Hence, on solving for area using herons formula, area = 49/2 = 24.5 unit²