Answer:
Step-by-step explanation:
If Samantha's earnings continue to increase at the same rate, this means that her earning is increasing arithmetically.
If she earned $550 in the first day, we can say the first term is $550
If she earned $750 on the third day, we can say the third term is $750
For us to know by how much her money is increasing, we need to find the common difference d formed by the sequence
550, x , 750
T1 = 550
T2 = x
T3 = 750
Common difference d = T2-T1 = T3-T2
x - 550 = 750 - x = d
Let's calculate the second term first i.e x
Since x - 550 = 750 - x = d
x - 550 = 750 - x
Collect like terms
x+x = 750+550
2x = 1300
x = 1300/2
x = 650
d = T2-T1
d = x - T1
d = 650-550
d = 100
Hence her money keeps increasing by $100 each day
Answer:
R72. 80
Step-by-step explanation:
1KG = R36, 40
2KG = R36.40 X 2
= R72. 80
Equation 1) 3x + 2y - 5z = 3
Equation 2) 4x - 2y - 3z = -10
Equation 3) 5x - 2y - 2z = -11
Add equation 1 with equation 2.
Equation 4) 7x - 8z = 7
Then subtract equation 3 from equation 2.
Equation 5) -x -z = 1
Multiply all of equation 5 with 7.
5) -7x - 7z = 7
4) 7x - 8z = 7
Add equations together.
z = 14
Plug in 14 for z in equation 4.
7x - 8z = 7
7x - 8(14) = 7
7x - 112 = 7
7x = 119
x = 17
Plug in 17 for x in equation 1, and 14 for z.
1) 3x + 2y - 5z = 3
3(17) + 2y - 5(14) = 3
51 + 2y - 70 = 3
2y - 19 = 3
2y = 22
y = 11
So, x = 17, y = 11, and z = 14
~Hope I helped!~
<span>4x^2 - 25
= (2x)^2 - 5^2 .................using a^2 - b^2 = (a+b)(a-b)
= (2x + 5)(2x - 5)</span>
Answer:
i think it's 37.7
Step-by-step explanation: