Answer:
(y - 2)²
Step-by-step explanation:
9y² - 12y + 4 ← is a perfect square of the form
(ax - b)² = a²x² - 2abx + b²
Compare like terms with 9y² - 12y + 4, thus
a² = 9 ⇒ a = 3
b² = 4 ⇒ b = 2 and
- 2ab = - 2 × 3 × 2 = - 12
Thus
9y² - 12y + 4 = (3y - 2)²
Answer:
The larger number is -6, the smaller number is -15
Step-by-step explanation:
We have two numbers, a and b.
We know that one number is larger than another by 9.
Then we can write:
a = b + 9
then a is larger than b by 9 units.
If the greater number is increased by 10 (a + 10) and the lesser number is tripled (3*b), the sum of the two would be -41:
(a + 10) + 3*b = -41
So we got two equations:
a = b + 9
(a + 10) + 3*b = -41
This is a system of equations.
One way to solve this is first isolate one variable in one of the two equations:
But we can see that the variable "a" is already isolated in the first equation, so we have:
a = b + 9
now we can replace that in the other equation:
(a + 10) + 3*b = -41
(b + 9) + 10 + 3*b = -41
now we can solve this for b.
9 + b + 10 + 3b = -41
(9 + 10) + (3b + b) = -41
19 + 4b = -41
4b = -41 -19 = -60
b = -60/4 = -15
b = -15
then:
a = b + 9
a = -15 + 9 = -6
a = -6
Answer:
D. The scale factor is 1:840
Step-by-step explanation:
Make 630 ft into inches, so 7560
Then make it 9/7560, which simplifies to 1/840
Answer:
Step-by-step explanation:
The upper right angle is supplement to 130° and a corresponding angle to (3x + 5)
130 + (3x + 5) = 180
3x + 5 = 50
3x = 45
x = 15
