Answer:
x = 4
Step-by-step explanation:
we know that 72 and (2x + 10) add up to 90
90-72 = 18
(2x + 10) = 18
2x = 8
x = 4
Let Daniel's age be 'x' years , hence, Lisa's age is (x - 5) years. Let Grandma's age be 'y' = 54 years.
Hence,
x(x - 5) = 2/3 × y
x² - 5x = 2 × 54 years / 3
x² - 5x = 36 years
x² - 5x - 36 = 0
∆ = (-5)² - 4(1)(-36) = 25 + 144 = 169
√∆ = √169 = 13

x1 = (5+13)/2, x2 = (5-13)/2
x1 = 9, x2 = -4
Since, age can't be negative,
Daniel's age = x = 9 years.
Answer:
They're both acute
Step-by-step explanation:
They both meausre less than 90°
A right angle would look like an L (it could be a flip L as well)
And an obtuse angle is anything bigger than a right angle
0.42z = 2.52
z = 2.52 / 0.42
z = 6
same as
z + 7.45 = 13.45
z = 13.45 - 7.45
z = 6
answer is top right z + 7.45 = 13.45