Answer:
number one. 186
number two. 36
Step-by-step explanation:
FOR NUMBER ONE:
the area of a trapezoid formula is 
where a and b are the bases and h is the height. so we have to add in the numbers into the formula
= <em>81</em>
and the paralellogram formula is b×h. where b is the base and h is height
15 × 7 = <em>105</em>
so the area of the figure is 81 + 105 is 186 in^2
FOR NUMBER TWO:
the area of the square formula is 
. where s is the side
4^2 = <em>16</em>
and for the paralellogram is b × h
4 × 5 = <em>20</em>
so the area of the figure is 16 +20 = 36 in^2
hope this helps! ;)
Answer:
392
Step-by-step explanation:
7(8) + 3(8)(14)
56 + 336
=392
*Brackets mean to multiply.
Answer:
Sister = 15 years old
Brother = 12 years old
Step-by-step explanation:
Right now, if the brother is B years old and the sister is S years old, B = (4/5)S because the ratio from brother to sister is 4:5, so if one unit is X, B = 4X and S = 5X
Three years ago, the brother was B-3 years old and the sister was S-3 years old. Keeping one unit as X, we have
B = 3X
S = 4X
B-3 = (3/4)(S-3)
Therefore, we have a system of equations
B = (4/5)S
B-3 = (3/4)(S-3)
Substitute (4/5)S for B into the second equation to only have one variable
(4/5)S - 3 = (3/4)(S-3)
(4/5)S - 3 = (3/4)S - 9/4
add 3 to both sides and subtract (3/4)S from both sides to isolate the variable and its coefficient
(1/20)S = 3/4
multiply both sides by 20 to isolate the S
S = 15
B = (4/5)S = 12
