A=1x3 means 1 row and 3 columns.
B=3x4 means 3 rows and 4 columns.
AB is a compatible multiplication because A has three columns and B has 3 rows.
However, BA is not a compatible multiplication because B has 4 columns while A has only 1 row.
The general trick is if you read the row/column of the two matrices as 1-3-3-4, and the two middle ones are identical, then AB would be a compatible multiplication. On the other hand, BA would read 3-4-1-3, since 4 and 1 are not identical, so it is not a valid multiplication.
Do remember 1x3 means 1 ROW and 3 COLUMNS.
21.
The angle has an opposite side of value 11 and an adjacent side of value x
We can then apply the formula tan 38° = opposite / adjacent
this gives us tan(38) = 11 / x
11/x = tan(38)
11 = x × tan(38)
x = 11 / tan(38)
x ≈ 14.1 (rounded to the nearest tenth)
And then we need to find the length of the hypotenuse, applying the theorem of Pythagoras. Let H be the hypotenuse, then :
H² = 14,1² + 11²
H² = 198,81 + 121
H = √(319,81)
H ≈ 17,9
Finally the area of the triangle will be (17,9 + 11) / 2 = 28,9 / 2 ≈ 14,45
You apply the same thing for 22 and 23
For 22 you use tan 55 = 15 / x
For 23 you use tan 23 = 7 / x
Good Luck !
Answer:
both are "not proportional
Step-by-step explanation:
when you divide y by x none of the numbers match up.
pls correct if wrong
Drawing a diagram will help you visualize how to solve the math problem
5. is 19.53 Use the Pythagorean Theorem. The length of the ladder is the hypotenuse and 19 is the vertical side and the 4.5 is the horizontal side.
7. y= 20.4
I don't know the rest.