Answer:
Step-by-step explanation:
19.
2x^2+x-6=0
x^2+x-12=0
(x+2)(2x-3)=0
x=-2,3/2
20.
x^2+8x+15=0
(x+3)(x+5)=0
x=-3,-5
Answer:
y<14/3
Step-by-step explanation:
−3y < −14
dividing both side by -3
-3y/-3 <-14/-3
y<14/3
Answer:
When x = 8.4 and y = .8 then 4x + 8y = 40
Step-by-step explanation:
4x + 8y = 40
y = .8
Let's solve for x by substituting .8 for y (since y is given)
4x + 8(.8) = 40
4x + 6.4 = 40 Subtract 6.4 from both sides.
4x + 6.4 - 6.4 = 40 - 6.4
4x = 33.6 Divide each side by 4
4x/4 = 33.6/4 4 cancels on the left because 4/4 = 1
x = 33.6/4
x = 8.4
So when x = 8.4 and y = .8 then 4x + 8y = 40
Answer: 131,400$
Step-by-step explanation:
The sale for first month is $500.
The sale increases by $10 each month, as modelled by the equation:
a_k=500+(k-1)10
where, k = 1 (first month)
k = 2 (second month)
.... and so on.
we have to calculate the sale for the first 10 years, that means for 10*12 = 120 months (1 year = 12 months)
Total sales = ∑ a_k
∑ a_k = ∑ (500+(k-1)10)
= 500k + ∑ (10k - 10)
= 500k + 10∑k - 10k
= 490k + 10∑k
= 490k + 10 {k*(k+1)/2}
= 490k + 5{k*(k+1)}
= 490k + 5k^2 + 5k
= 5k^2 + 495k
∴∑ a_k = 5k^2 + 495k
For calculating the total sales of 10 years, we will put the value of k = 120 (120th month after the first month)
= 5*(120*120) + 495*120
= 72,000 + 59, 400
= 131,400$
First of all, triangles angles add up to 180 degrees.
BCD=120. To find BCA subtract 180-120 to get 60 degrees.
We know what ABC is, it equals 85, so far we have 2 angles.
Lets add them up, 85+60=145
Since the angles must add up to equal 180 we're going to subtract 180-145
Which equals 35, BAC=35 degrees.
-Seth