We will use a method of substitution.
y = 5/2 x + 2
2 y = 5 x + 4 ⇒ 2 ( 5/2 x + 2 )= 5 x + 4
5 x + 4 = 5 x + 4
0 x = 0 ⇒ x, y ∈ R
Answer: D)
This system has infinitely many solutions.
c is correct.
(Pe)²/(De)³=(Pj)²/(Dj)³ (Pe stands for period of Earth, De for Distance of Earth from Sun,
Because Dj=5.2De
(Pe)²/(De)³=(Pj)²/(5.2De)³
Pj=√(5.2³)(Pe)²=(5.2³)(1)² ≈11.9 =(note: Pe=1 earth year)
Answer:
amount invested in the account that earns 10% interest = Rs 3500
amount invested in the account that earns 8% interest =Rs 5500
Step-by-step explanation:
Two equations can be derived from the question
x + y = 9000 equation 1
0.08x + 0.1y = 790 equation 2
x = amount invested in the account that earns 8% interest
y = amount invested in the account that earns 10% interest
multiply equation 1 by 0.08
0.08x + 0.08y = 720 equation 3
subtract equation 3 from 2
0.02y = 70
divide both sides of the equation by 0.02
y = 70 / 0.02
y = 3500
Substitute for y in equation 1
x + 3500 = 9000
x = 9000 - 3500 = 5500
Answer:
4
_
3
Step-by-step explanation:
4 times 7 = 28
3 times 7 = 21
It will take him 21 days to make 28 bird houses.