Answer:
C . 4
Step-by-step explanation:
step 1 : -3 multiply with inside of the ( 7x-5 )
= -21x + 15
step 2 : then it will be 21x + 15 = 87 + 3x
step 3 : switch between the odds into like this
21x - 3x = 87 - 15
step 4 : subtract it all
18x = 72
step 5 : bring 18 to the other side
x = 72/18
step 6 : to find the ans of x is just calculate them
x = 72 ÷ 18
= 4
Or you can do like these ⬇️
-3 ( 7x - 15 ) = 87 + 3x
21x + 15 = 87 + 3x
21x - 3x = 87 - 15
18x = 72
x = 72/18 or 72÷18
x = 4
Answer:
Rate = 6.56%
Step-by-step explanation:
Principal (P) = $5000
Interest (I) = $6312
Time (T) = 4 years
Rate (r) = ?
This question is involves simple interest and with the formula, we can easily plug in the values to find the rate.
S.I = P(1 + rt)
S.I = simple interest
P = principal
R = Rate
T = Time
6312 = 5000(1 + r*4)
6312 = 5000 + 5000*4r
6312 - 5000 = 20000r
1312 = 20000r
r = 1312 / 20000
r = 0.0656
Rate are calculated in percentage hence we'll multiply it by 100
R = 6.56%
Answer:
the answer is 3
Step-by-step explanation:
because 3x3= 9
5x3=15 so 15-9=6
She worked as a carpenter for 12 hours and as a blacksmith for 18 hours.
Assuming you mean she earned $20 as a carpenter and $25 as a blacksmith per hour, with a total of 30 hours for $690,
let c represent carpenter hours and b for blacksmith hours.
20c + 25b = 690
c + b = 30
Subtract b from each side so that c = 30 - b
Plug this value into the first equation
20(30 - b) + 25b = 690
600 - 20b + 25b = 690
600 + 5b = 690
5b = 90
b = 18
To find c, plug this value of b into the other equation
c + 18 = 30
c = 12
