4 x 3 = 12
1 x 3 = 3
12 + 3 = 15
answer
15 square units
We know that:
∠ABC=∠BCA=xº
∠BDC=∠BCD=xº
1) we have to find the angle ∠DBC:
∠BDC+∠BCD+∠DBC=180º
xº+xº+∠DBC=180º
2xº+∠DBC=180º
∠DBC=180º-2xº
2) we have to find the angle ∠ABD:
∠ABD=∠ABC-∠DBC
∠ABD=xº-(180º-2x)
∠ABD=xº-180º+2xº
∠ABD=3xº-180º
Answer: ∠ABD=3xº-180º
Hello there! I can help you!
7. Okay. So the computer was originally $1,080, and the discount is 20%, but David would still have to pay 80% of the original price. To find the sale price, let's multiply. 1,080 * 80% (0.8) is 864. The sale price of the compuet is $864, but now we must add the sales tax to find the total price. We will multiply by 108%, because 100% (representing the price + 8% is 108%, and doing this will get us stright to the total price. 864 * 108% (1.08) is 933.12. There. David paid a total price of $933.12 for the computer.
8. Okay. So we are looking for the amount of discount for the sweater Suzanne bought. First off, let's subtract the prices to find the difference. 40 - 25 is 15. Now, let's divide that by 40 (the original price) to find the discount. 15/40 is 0.375. Or 37.5% when converted into a percentage. There. Suzanne received a 37.5% discount on the sweater when she bought it.
9. So the car was bought for x dollars. 0.88 represents 88%, so the value of the car is 88% of the previous year. An expression that is a way to describe the change in car value is x * (100 - 0.12)^t, because you car loses 12% of the remaining value each year, which leaves 88% of it remaining, and having the t as the exponent represents the number of years. That expression helps find the value of the car currently and can help you compare the values.
Xy= 120
x= 7+y
(7+y)(y) = 120
y^2 + 7y - 120 = 0
(y + 15) (y - 8) = 0
Since we are finding two positive numbers,
If y= 8 then x= 15
The two numbers are 8 and 15
I might be wrong but 9
9*2=18
18+7= 25
25 square root = 5
Answer is 9
