Answer:
Step-by-step explanation:
A rectangle had a length of 2x-7 and a width of 3x+8y
Perimeter P = 2(l + w)
P = 2(2x - 7 + 3x + 8y)
P = 2(5x + 8y - 7)
P= 10x + 16y - 14
Answer:
She has 60% of money left.
Step-by-step explanation:
You have to find out how much Php that Lei has left :
Php 150 - Php 48 - Php 12 = Php 90
She has a remaining of Php 90. Next, you have to find the percentage by dividing hy original amount and then, multiply by 100 :
(90/150)×100 = (3/5)×100 = 60%
Answer:
x = -2, y=1
Step-by-step explanation:
x-7y=-9---------------------equation 1
-x+8y=10-------------------equation 2
From equation 1, make x the subject of formula
x=7y-9----------------------equation 3
substituting x=7y-9 in equation 2,
-(7y-9)+8y=10
Expanding bracket
-7y+9+8y=10
Collecting like terms
8y-7y=10-9
y=1
substituting y=1 in 3
x=7(1)-9
x=7-9
x=-2
Answer:
A = 40°
B = 50°
Step-by-step explanation:
If cos A = sin B, then A + B = 90
So, 2x/3 + 20 + 2x - 10 = 90
2x + 60 + 6x - 30 = 270
8x + 30 = 270
8x = 240
x = 30
2x/3 + 20 = 60/3 + 20 = 20 + 20 = 40
2x - 10 = 2(30) - 10 = 60 - 10 = 50 or 90 - 40 = 50
The equation should be 7x^2 -x-9=0
